编辑client.ovpn客户端配置文件：
vim client.ovpn
删除或者注释以下几行内容：
ca ca.crt 改为：#ca ca.crt
cert client.crt 改为：#cert client.crt
key client.key 改为：#key client.key
tls-auth ta.key 1 改为：#tls-auth ta.key 1
在最后面添加以下内容：
<ca>
ca.crt 文件内容
</ca>
<cert>
client.crt 文件内容
</cert>
<key>
client.key 文件内容
</key>
key-direction 1
<tls-auth>
ta.key 文件内容
</tls-auth>
复制各文件里的内容到相应的位置即可！保存退出！！
..
系统提供的常用注解清单：
1、@RequestParam绑定单个请求参数值；
2、@PathVariable绑定URI模板变量值；
3、@CookieValue绑定Cookie数据值;
4、@RequestHeader绑定请求头数据；
5、@ModelAttribute绑定参数到命令对象；
6、@SessionAttributes绑定命令对象到session；
7、@RequestBody绑定请求的内容区数据并能进行自动类型转换等。
8、@RequestPart绑定“multipart/data”数据，除了能绑定@RequestParam能做到的请求参数外，还能绑定上传的文件等。
除上述提到的注解，我们还可以通过如HttpServletRequest等API得到请求数据。
图示：
RequestMapping是一个用来处理请求地址映射的注解，可用于类或方法上。用于类上，表示类中的所有响应请求的方法都是以该地址作为父路径。
RequestMapping注解有六个属性，下面我们把她分成三类进行说明（下面有相应示例）。
1、 value， method；
value： 指定请求的实际地址，指定的地址可以是URI Template 模式（后面将会说明）；
method： 指定请求的method类型， GET、POST、PUT、DELETE等；
2、consumes，produces
consumes： 指定处理请求的提交内容类型（Content-Type），例如application/json, text/html;
produces: 指定返回的内容类型，仅当request请求头中的(Accept)类型中包含该指定类型才返回；
3、params，headers
params： 指定request中必须包含某些参数值是，才让该方法处理。
headers： 指定request中必须包含某些指定的header值，才能让该方法处理请求。
@Resource和@Autowired都是做bean的注入时使用，其实@Resource并不是Spring的注解，它的包是javax.annotation.Resource，需要导入，但是Spring支持该注解的注入。
代表的是：该Controller的所有方法在调用前，先执行此@ModelAttribute方法，可用于注解和方法参数中，可以把这个@ModelAttribute特性，应用在BaseController当中，所有的Controller继承BaseController，即可实现在调用Controller时，先执行@ModelAttribute方法。
用于将请求URL中的模板变量映射到功能处理方法的参数上，即取出uri模板中的变量作为参数
@requestParam主要用于在SpringMVC后台控制层获取参数，类似一种是request.getParameter("name")，它有三个常用参数：defaultValue = "0", required = false, value = "isApp"；defaultValue 表示设置默认值，required 铜过boolean设置是否是必须要传入的参数，value 值表示接受的传入的参数类型。
作用： 该注解用于将Controller的方法返回的对象，通过适当的HttpMessageConverter转换为指定格式后，写入到Response对象的body数据区。
使用时机：返回的数据不是html标签的页面，而是其他某种格式的数据时（如json、xml等）使用；
相当于通用的注解，当不知道一些类归到哪个层时使用，但是不建议。
用于注解dao层，在daoImpl类上面注解。
使用 ServletRequest/HttpServletRequest 和 ServletResponse/HttpServletResponse：
public String requestOrResponse (
ServletRequest servletRequest, HttpServletRequest httpServletRequest,
ServletResponse servletResponse, HttpServletResponse httpServletResponse
)
使用 InputStream/OutputStream：
public void inputOrOutBody(InputStream requestBodyIn, OutputStream responseBodyOut)
throws IOException {
responseBodyOut.write("success".getBytes());
}
requestBodyIn：获取请求的内容区字节流，等价于request.getInputStream()
responseBodyOut：获取相应的内容区字节流，等价于response.getOutputStream()
使用 Reader/Writer：
public void readerOrWriteBody(Reader reader, Writer writer)
throws IOException {
writer.write("hello");
}
使用 @RequestParam/@SessionAttributes/@CookieValue：
public void readerOrWriteBody(@RequestParam String uid, @SessionAttributes String uid){}
参考：
https://www.cnblogs.com/leskang/p/5445698.html
..
一、SNAT源地址转换
1、原理：在路由器后（PSOTROUTING）将内网的ip地址修改为外网网卡的ip地址。
2、应用场景：共享内部主机上网。
3、设置SNAT：网关主机进行设置。
（1）设置ip地址等基本信息。
（2）开启路由功能：
sed -i '/ip-forward/s/0/1/g'
sysctl -p
（3）编写规则：
iptables -t nat -I POSTROUTING -o 外网网卡 -s 内网网段 -j SNAT --to-source 外网ip地址 #适用于外网ip地址固定场景
iptables -t nat -I POSTROUTING -o 外网网卡 -s 内网网段 -j MASQUERADE #适用于共享动态ip地址上网（如adsl拨号，dhcp获取外网ip）
（4）做好安全控制：使用FORWARD时机进行控制，严格设置INPUT规则。
二、DNAT目的地址转换：
1、原理：在路由前（PREROUTING）将来自外网访问网关公网ip及对应端口的目的ip及端口修改为内部服务器的ip及端口，实现发布内部服务器。
2、应用场景：发布内部主机服务。
3、设置DNAT：网关主机上设置。
（1）设置ip、开启路由、设置SNAT
（2）编写防火墙规则：
iptables -t nat -I PREROUTING -i 外网网卡 -d 外网ip tcp --dport 发布的端口 -j DNAT --to-destination 内网服务ip:端口
NAT network address translation
仅从报文请求来看，可以分为：
SNAT 源地址转换
DNAT 目标地址转换
PNAT 端口转换
NAT server：能根据需要实现SNAT DNAT PNAT
并非是用户空间的进程完成转换功能，靠的是内核中的地址转换规则
私有IP客户端访问互联网的方法
SNAT 、PROXY
SNAT：主要用于实现内网客户端访问外部主机时使用（局域网上网用）
定义在POSTROUTING链上
iptables -t nat -A postrouting -s 内部网络地址或主机地址 -j SNAT --to-source NAT服务器上的某外部地址
另外一个target
MASQUERADE地址伪装（适用于PPPOE拨号上网，假设eth1是出口）
iptables -t nat -A postrouting -s 内部网络或主机地址 -o eth1 -j MASQUERADE
DNAT：主要用于内部服务器被外网访问（发布服务）
定义在PREROUTING
iptables -t nat -A PREROUTING -d NAT服务器的某外部地址 -p 某协议 --dport 某端口 -j DNAT --to-destination 内网服务器地址[:port]
注意：NAT服务器需要打开数据转发
echo 1 > /proc/sys/net/ipv4/ip_forward
或者修改/etc/sysctl.conf net.ipv4.ip_forward = 1
实验操作
SNAT、DNAT
实验一：
SNAT
规划主机A 作为SNAT server
eth0 ip地址172.20.1.10（外部地址），eth1 192.168.1.1（内部地址）
主机B当做局域网内主机
eth0 ip地址192.168.1.2 默认路由要指向192.168.1.1
SNAT server：
[root@localhost ~]# iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -j SNAT --to-source 172.20.1.10
#上面和我们实例操作相同
[root@localhost ~]# echo 1 > /proc/sys/net/ipv4/ip_forward
主机B ping外部的其它主机（172.20.1.20模拟互联网上的主机）
DNAT
[root@nat ~]# iptables -t filter -F
[root@nat ~]# iptables -t nat -F
[root@nat ~]# iptables -t nat -A PREROUTING -d 10.1.249.125 -p tcp --dport 80 -j DNAT --to-destination 192.168.2.4
Chain PREROUTING (policy ACCEPT)
target prot opt source destination
DNAT tcp -- 0.0.0.0/0 10.1.249.125 tcp dpt:80 to:192.168.2.4
[root@nat ~]# netstat -tln | grep "\<80\>" 此时本机上并没有开放80端口
[root@wai ~]# curl http://10.1.249.125
hello --> 此时我们访问为 nat 主机上的80端口 由上面可知,此服务器上并没有开放80,而是将请求送往 后端服务器
实体案例
我们有一台机器A可以上外网，配置eth0=192.168.1.1,eth1=222.13.56.192
有6台机器只有内网IP ，分别是192.168.1.102~192.168.1.108,想让这6台机器通过机器A上网
在机器A 防火墙上配置如下即可
/sbin/iptables -t nat -I POSTROUTING -s 192.168.1.101 -j SNAT --to-source 222.13.56.192
/sbin/iptables -t nat -I POSTROUTING -s 192.168.1.102 -j SNAT --to-source 222.13.56.192
/sbin/iptables -t nat -I POSTROUTING -s 192.168.1.103 -j SNAT --to-source 222.13.56.192
/sbin/iptables -t nat -I POSTROUTING -s 192.168.1.104 -j SNAT --to-source 222.13.56.192
/sbin/iptables -t nat -I POSTROUTING -s 192.168.1.105 -j SNAT --to-source 222.13.56.192
/sbin/iptables -t nat -I POSTROUTING -s 192.168.1.108 -j SNAT --to-source 222.13.56.192
在 6台机器上路由显示
route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 em1
169.254.0.0 0.0.0.0 255.255.0.0 U 1002 0 0 em1
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 em1
网络应用程序，分为前端和后端两个部分。当前的发展趋势，就是前端设备层出不穷（手机、平板、桌面电脑、其他专用设备......）。
因此，必须有一种统一的机制，方便不同的前端设备与后端进行通信。
这导致API构架的流行，甚至出现"API First"的设计思想。
RESTful API是目前比较成熟的一套互联网应用程序的API设计理论。
我以前写过一篇《理解RESTful架构》，探讨如何理解这个概念。
今天，我将介绍RESTful API的设计细节，探讨如何设计一套合理、好用的API。我的主要参考了两篇文章（1，2）。
API与用户的通信协议，总是使用HTTPs协议。
应该尽量将API部署在专用域名之下。
https://api.example.com
如果确定API很简单，不会有进一步扩展，可以考虑放在主域名下。
https://example.org/api/
应该将API的版本号放入URL。
https://api.example.com/v1/
另一种做法是，将版本号放在HTTP头信息中，但不如放入URL方便和直观。Github采用这种做法。
路径又称"终点"（endpoint），表示API的具体网址。
在RESTful架构中，每个网址代表一种资源（resource），所以网址中不能有动词，只能有名词，而且所用的名词往往与数据库的表格名对应。一般来说，数据库中的表都是同种记录的"集合"（collection），所以API中的名词也应该使用复数。
举例来说，有一个API提供动物园（zoo）的信息，还包括各种动物和雇员的信息，则它的路径应该设计成下面这样。
- https://api.example.com/v1/zoos
- https://api.example.com/v1/animals
- https://api.example.com/v1/employees
对于资源的具体操作类型，由HTTP动词表示。
常用的HTTP动词有下面五个（括号里是对应的SQL命令）。
- GET（SELECT）：从服务器取出资源（一项或多项）。
- POST（CREATE）：在服务器新建一个资源。
- PUT（UPDATE）：在服务器更新资源（客户端提供改变后的完整资源）。
- PATCH（UPDATE）：在服务器更新资源（客户端提供改变的属性）。
- DELETE（DELETE）：从服务器删除资源。
还有两个不常用的HTTP动词。
- HEAD：获取资源的元数据。
- OPTIONS：获取信息，关于资源的哪些属性是客户端可以改变的。
下面是一些例子。
- GET /zoos：列出所有动物园
- POST /zoos：新建一个动物园
- GET /zoos/ID：获取某个指定动物园的信息
- PUT /zoos/ID：更新某个指定动物园的信息（提供该动物园的全部信息）
- PATCH /zoos/ID：更新某个指定动物园的信息（提供该动物园的部分信息）
- DELETE /zoos/ID：删除某个动物园
- GET /zoos/ID/animals：列出某个指定动物园的所有动物
- DELETE /zoos/ID/animals/ID：删除某个指定动物园的指定动物
如果记录数量很多，服务器不可能都将它们返回给用户。API应该提供参数，过滤返回结果。
下面是一些常见的参数。
- ?limit=10：指定返回记录的数量
- ?offset=10：指定返回记录的开始位置。
- ?page=2&per_page=100：指定第几页，以及每页的记录数。
- ?sortby=name&order=asc：指定返回结果按照哪个属性排序，以及排序顺序。
- ?animal_type_id=1：指定筛选条件
参数的设计允许存在冗余，即允许API路径和URL参数偶尔有重复。比如，GET /zoo/ID/animals 与 GET /animals?zoo_id=ID 的含义是相同的。
服务器向用户返回的状态码和提示信息，常见的有以下一些（方括号中是该状态码对应的HTTP动词）。
- 200 OK - [GET]：服务器成功返回用户请求的数据，该操作是幂等的（Idempotent）。
- 201 CREATED - [POST/PUT/PATCH]：用户新建或修改数据成功。
- 202 Accepted - [*]：表示一个请求已经进入后台排队（异步任务）
- 204 NO CONTENT - [DELETE]：用户删除数据成功。
- 400 INVALID REQUEST - [POST/PUT/PATCH]：用户发出的请求有错误，服务器没有进行新建或修改数据的操作，该操作是幂等的。
- 401 Unauthorized - [*]：表示用户没有权限（令牌、用户名、密码错误）。
- 403 Forbidden - [*] 表示用户得到授权（与401错误相对），但是访问是被禁止的。
- 404 NOT FOUND - [*]：用户发出的请求针对的是不存在的记录，服务器没有进行操作，该操作是幂等的。
- 406 Not Acceptable - [GET]：用户请求的格式不可得（比如用户请求JSON格式，但是只有XML格式）。
- 410 Gone -[GET]：用户请求的资源被永久删除，且不会再得到的。
- 422 Unprocesable entity - [POST/PUT/PATCH] 当创建一个对象时，发生一个验证错误。
- 500 INTERNAL SERVER ERROR - [*]：服务器发生错误，用户将无法判断发出的请求是否成功。
状态码的完全列表参见这里。
如果状态码是4xx，就应该向用户返回出错信息。一般来说，返回的信息中将error作为键名，出错信息作为键值即可。
{
error:"Invalid API key"
}
针对不同操作，服务器向用户返回的结果应该符合以下规范。
- GET /collection：返回资源对象的列表（数组）
- GET /collection/resource：返回单个资源对象
- POST /collection：返回新生成的资源对象
- PUT /collection/resource：返回完整的资源对象
- PATCH /collection/resource：返回完整的资源对象
- DELETE /collection/resource：返回一个空文档
RESTful API最好做到Hypermedia，即返回结果中提供链接，连向其他API方法，使得用户不查文档，也知道下一步应该做什么。
比如，当用户向api.example.com的根目录发出请求，会得到这样一个文档。
{
"link": {
"rel": "collection https://www.example.com/zoos",
"href": "https://api.example.com/zoos",
"title": "List of zoos",
"type":"application/vnd.yourformat+json"
}
}
上面代码表示，文档中有一个link属性，用户读取这个属性就知道下一步该调用什么API了。rel表示这个API与当前网址的关系（collection关系，并给出该collection的网址），href表示API的路径，title表示API的标题，type表示返回类型。
Hypermedia API的设计被称为HATEOAS。Github的API就是这种设计，访问api.github.com会得到一个所有可用API的网址列表。
{
"current_user_url": "https://api.github.com/user",
"authorizations_url": "https://api.github.com/authorizations",
// ...
}
从上面可以看到，如果想获取当前用户的信息，应该去访问api.github.com/user，然后就得到了下面结果。
{
"message": "Requires authentication",
"documentation_url": "https://developer.github.com/v3"
}
上面代码表示，服务器给出了提示信息，以及文档的网址。
（1）API的身份认证应该使用OAuth 2.0框架。
（2）服务器返回的数据格式，应该尽量使用JSON，避免使用XML。
（完）
文章摘自： http://www.ruanyifeng.com/blog/2014/05/restful_api.html
参考：
理解RESTful架构 http://www.ruanyifeng.com/blog/2011/09/restful.html
好RESTful API的设计原则 https://www.cnblogs.com/moonz-wu/p/4211626.html
http://www.informit.com/articles/article.aspx?p=1566460
..
Java Servlet是与平台无关的服务器端组件，运行于Servlet容器中(如Tomcat)，Servlet容器负责Servlet和客户端的通信以及调用Servlet的方法，Servlet和客户端的通信采用“请求/响应”的模式。Servlet可完成以下功能：
1、创建并返回基于客户请求的动态HTML页面。
2、创建可以嵌入到现有HTML页面中的HTML片段。
3、与其它服务器资源（如数据库或基于Java的应用程序）进行通信。
4、接收多个客户端的输入，并将结果广播到多个客户端上，例如，Servlet可以实现支持多个参与者的游戏服务器。
5、根据客户请求采用特定的MIME（Multipurpose Internet Mail Extensions）类型对数据过滤，例如进行图像格式转换。
Servlet的框架由两个包组成：javax.servlet和javax.servlet.http。在javax.servlet包中定义了所有Servlet类必须实现或扩展的通用接口和类。在javax.servlet.http包中定义了采用HTTP协议通信的HttpServlet类。
Servlet框架的核心是javax.servlet.Servlet接口，所有的Servlet类都必须实现这个接口。Servlet接口定义的方法如下：
1、init方法，负责初始化Servlet对象。
2、service方法，负责响应客户端的请求。
3、destroy方法，当Servlet对象退出生命周期时，负责释放占用的资源。
4、getServletConfig方法，获得ServletConfig接口，可以得到Servlet的相关参数。
5、getServletInfo方法，获得Servlet的相关信息。
在javax.servlet包中，GenericServlet类实现了Servlet接口，在javax.servlet.http包中，HttpServlet类扩展了GenericServlet
类。当用户开发自己的Servlet时，必须扩展以上两个类中的一个，如果扩展自GenericServlet类，则必须自己实现service方法，
如果扩展自HttpServlet类，则不需要自己实现service方法，因为HttpServlet类已经实现了该方法。
GenericServlet类的service方法是一个抽象方法，只有两个参数：ServletRequest和ServletResponse。HttpServlet类的service方法也只有两个参数：HttpServletRequest和HttpServletResponse。HttpSevletRequest接口和HttpResponse接口分别扩展自ServletRequest和ServletResponse接口，都提供了与特定协议HTTP相关的数据。
ServletRequest接口的方法如下：
getAttribute 获得属性值
getContentType 获得客户请求数据的MIME类型。
getInputStream 获得可以读取客户请求数据的输入流。
getParameter 获得参数值
getRemoteAddr 获得客户端的IP
getRemoteHost 获得客户端的主机名
getRemotePort 获得客户端的端口
setAttribute 设置属性值。
ServletResponse接口的方法如下：
getOutputStream 获得可以向客户羰发送二进制数据的输出流对象ServletOutputStream
getWriter 获得可以向客户端发送字符数据的PrintWriter对象
getCharacterEncoding 获得Servlet发送的响应数据的字符编码
getContentType 返回Servlet发送的响应数据的MIME类型
setCharacterEncoding 设置Servlet发送的响应数据的字符编码。
setContentType 设置Servlet发送的响应数据的MIME类型。
Servlet的init方法有如下两种形式：
public void init(ServletConfig config) throws ServletException
public void init() throws ServletException
在Servlet的初始化分阶段，Servlet容器会为Servlet创建一个ServletConfig对象，用来存放Servlet的初始化配置信息，如Servlet的初始参数。如果Servlet覆盖了带参数的init方法，则必须在函数体内先调用super.init(config); 以确保config参数引用了ServletConfig对象。如果Servlet覆盖了没有带参数的init方法，则不需要调用super.init(); 方法，可以通过调用getServletConfig()方法来获得ServletConfig对象。
Servlet容器会为Web应用创建一个唯一的全局的ServletContext对象，可以把它看成是一个Web应用的服务器端组件的共享内存。它有如下方法：
etAttribute(String name,Object obj) 将一个对象与一个属性名绑定，并存放到
ServletContext中
getAttribute(String name) 获得指定名称的属性值。
removeAttribute(String name) 删除指定名称的属性。
getAttributeNames() 返回所有属性名的一个Enumeration对象。
getInitParameter(String name) 获得指定名称的参数值,该参数是Web应用的初始化参数.
getInitParameterNames() 返回Web应用的所有初始化参数的名称的Enumeration对象.
getMimeType(String file) 返回文件的MIME类型.
getRealPath(String path) 返回网络路径path对应的文件系统路径.
getServerInfo() 返回Servlet容器的名称和版本
注意: 一般在HptpServlet的子类中,将doPost方法的实现合并到doGet方法中,也就是在doPost方法中简单地调用doGet方法.因为一般情况下对于Get和Post请求,它们都是一样的处理.
编译了Servlet后,将它打包成jar放到WEB-INF/lib目录下,或将Servlet的class文件放到WEB-INF/classes/目录下,再在WEB-INF/web.xml配置文件中配置这些servlet,就可以在Web应用中访问servlet了,配置如下:
<servlet>
<servlet-name>my_servlet</servlet-name>
<servlet-class>com.mycompany.ServletClass1</servlet-class>
< init-param> <!--定义servlet的初始化参数, 可以有多个init-param参数-->
< param-name>iParam< /param-name>
< param-value>2< /param-value>
< /init-param>
< load-on-startup>2< /load-on-startup> <!--定义servlet的加载顺序-->
</servlet>
<servlet-mapping>
<servlet-name>my_servlet</servlet-name>
<url-pattern>*.hello</url-pattern>
</servlet-mapping>
Session相关
在Servlet API中定义了javax.servlet.http.HttpSession接口，Servlet容器必须实现这一个接口。当一个Session开始时，Servlet容器将创建一个HttpSession对象，在HttpSession对象中可以存放客户状态的信息。Servlet容器为HttpSession对象分配一个唯一的标识符，叫做Session ID，Servlet容器把Session ID作为Cookie保存在客户的浏览器中，每次客户发出HTTP请求时，Servlet容器可以从HttpRequest对象中读取Session ID，然后根据Session ID找到相应的HttpSession对象，从而获得客户的状态信息。HttpSession接口有如下方法：
getId() 返回Session ID
invalidate() 使当前的Session失效，Servlet容器会释放HttpSession对象占用的资源。
setAttribute(String name,Object obj) 将一对name/value属性保存到HttpSession对象中。
getAttribute(String name) 返回名字为name的属性值。
getAttributeNames() 返回HttpSession对象中所有的属性名。
isNew() 判断这个Session是不是新创建的。
setMaxInactiveInterval() 设定Session可以处于不活动状态的最大时间（以秒为单位）， 超过这个时间，Session就会自动失效，如果设置为负数，则不 限制Session的不活动状态时间。
getMaxInactiveInterval() 返回Session可以处于不活动状态的最大时间。
当客户第一次访问Web应用中支持Session的某个页面时，就会开始一个新的Session，接下来，当客户浏览这个Web应用的其它页面时，始终处于同一个Session中。以下情况之一，Session就会失效：
1、客户端关闭浏览器。
2、Session过期，即客户在指定的最大时间内没有与Web服务器交互。
3、服务器端调用了HttpSession的invalidate()方法。
如果客户端浏览器不支持或禁用Cookie，则Servlet容器无法从客户端浏览器中取得作为Cookie的Session ID，也就无法跟踪客户的状态，因此客户端的每次请求支持Session的JSP页面时，Servlet容器都会创建一个新的HttpSession对象。对于这种情况，需要通过HttpServletResponse的encodeURL()方法重写客户请求的URL，它把Session ID添加到URL信息中，也就是说，对于支持Session的JSP页面中的所有连接URL，都要调用encodeURL()方法来重写这些URL，例如：
对于<a href=”login.jsp”/>应该改为<a href=”<%=response.encodeURL(“login.jsp”)%>”/>
这样，即使客户禁用Cookie，也能使用Session来跟踪客户的状态信息了。
Session的持久化：
Session的持久化就是将HttpSession对象从内存中转移到文件系统或数据库中，这样做的好处是：减少系统资源的占用，如果Servlet容器突然关闭或重启，或Web应用重启，这些持久化了的HttpSession对象可以再重新加载进来，对于客户端，还是使用同一个Session。
Session的持久化是由Session Manager来管理的，Tomcat提供了两个实现类：
l org.apache.catalina.session.StandarManager
l org.apache.catalina.session.PersistentManager
1、StandarManager是默认的Session Manager。它的实现机制是：当Tomcat服务器关闭或重启，或Web应用被重新加载时，会将内存中所有的HttpSession对象保存到文件系统中，默认的文件路径是：%CATALINA_HOME%\work\Catalina\<applicaton-name>\SESSIONS.ser
重启Tomcat后，Tomcat服务器把SESSIONS.ser中的持久化HttpSession对象加载到内存中。
2、PersistentManager能够把HttpSession对象保存到Session Store中，它提供了比较StandarManager更灵活的管理功能，具有容错能力，控制内存中HttpSession对象的数目等。
Tomcat实现Session Store的接口为org.apache.catalina.session.Store，目前提供了两个实现这一接口的类：org.apache.catalina.session.FileStore和org.apache.catalina.session.JDBCStore。FileStore会将HttpSession对象保存到文件系统中；而JDBCStore则将HttpSession对象保存到数据库表中。
下面给出这两个类的配置：
配置FileStore：
在server.xml中，在Web应用的<Context>元素加入<Manager>元素，例如：
<Context path=”/helloapp” docBase=”helloapp” debug=”0” reloadable=”true”>
<Manager className=”org.apache.catalina.session.PersistentManager”>
debug=0;
saveOnRestart=”true”
maxActiveSessions=”-1”
minIdleSwap=”-1”
maxIdleSwap=”-1”
maxIdleBackup=”-1”
<Store className=”org.apache.catalina.session.FileStore” directory=”mydir”/>
</Manager>
</Context>
|
属性 |
作用 |
|
className |
指定Session Manager的实现类名，或Session Store的实现类名 |
|
debug |
设定Session Manager采用的跟踪级别，取值0到99，越小越跟踪信息越少，发布产品时，应该设置为0，以提高性能。 |
|
saveOnRestart |
如果为true，则当Tomcat关闭时，所有的有效HttpSession对象都保存到Session Store中；当Tomcat重启时，加载这些HttpSession对象。 |
|
maxActiveSessions |
设置处于活动状态的Session的最大数目，如果超过这一数目，Tomcat把一些超过的Sessin对象保存到Session Store中。-1表示不限制。 |
|
minIdleSwap |
Session处于不活动状态的最小时间，单位为秒，超过这一时间，Tomcat有可能把这个Session对象移到Session Store中。 |
|
maxIdleSwap |
Session处于不活动状态的最大时间，超过这一时间，Tomcat就一定会将这个Session对象移到Session Store中。 |
|
maxIdleBackup |
Session处于不活动状态的最大时间，超过这一时间，Tomcat就就会将这个Session对象拷贝到Session Store中进行备份。 |
|
directory |
指定Session Store在哪个文件系统目录下存放持久化的Session对象的信息，文件名是Session ID.session。 |
配置JDBCStore:
在server.xml中，在Web应用的<Context>元素加入<Manager>元素，例如：
<Context path=”/helloapp” docBase=”helloapp” debug=”0” reloadable=”true”>
<Manager className=”org.apache.catalina.session.PersistentManager”>
debug=0;
saveOnRestart=”true”
maxActiveSessions=”-1”
minIdleSwap=”-1”
maxIdleSwap=”-1”
maxIdleBackup=”-1”
<Store className=”org.apache.catalina.session.JDBCStore”
driverName=”com.mysql.jdbc.Driver”
connectionURL=”jdbc:mysql://localhost:3306/demo?user=root password=1234”
sessionTable=”tomcat_sessions”
sessionIdCol=”session_id”
sessionDataCol=”session_data”
sessionValidCol=”session_valid”
sessionMaxInactiveCol=”max_inactive”
sessionLastAccessedCol=”last_access”
sessionAppCol=”app_name”
checkInterval=”60”
debug=”0”
/>
</Manager>
</Context>
说明：上面的元素属性的含义与FileStore的相同，上面的配置假设在MySQL服务器上的demo数据库的tomcat_sessions表中存放持久化Session对象的信息，这个表的结构如下：
CREATE TABLE tomcat_sessions(
session_id VARCHAR(10) NOT NULL PRIMARY KEY,
session_data MEDIUMBLOB,
session_valid CHAR(1) NOT NULL,
max_inactive INT NOT NULL,
last_access BIGINT NOT NULL,
app_name VARCHR(255),
KEY kapp_name(app_name)
);
Filter相关
Servlet过滤器是在Java Servlet规范2.3中定义的，它能够对Servlet容器的请求和响应对象进行检查和修改，它在Servlet被调用之前检查Request对象，修改Request Header和Request内容；在Servlet被调用之后检查Response对象，修改Response Header和Response内容。Servlet过滤器负责过滤的Web组件可以是Servlet、JSP或HTML文件，具有以下特点：
l Servlet过滤器可能检查和修改ServletRequest和ServletResponse对象
l 可以指定Servlet过滤器和特定的URL关联，只有当客户请求访问此URL时，才会触发该过滤器工作
l 多个Servlet过滤器可以被串联起来，形成管道效应，协同修改请求和响应对象
l 所有支持Java Servlet规范2.3的Servlet容器，都支持Servlet过滤器
所有的Servlet过滤器类都必须实现javax.servlet.Filter接口。该接口定义了以下3个方法：
l init(FilterConfig) 这是Servlet过滤器的初始化方法，Servlet容器创建Servlet过滤器实例后就会调用这个方法。在这个方法中可以通过FilterConfig来读取web.xml文件中Servlet过滤器的初始化参数。
l doFilter(ServletRequest, ServletResponse, FilterChain) 这是完成实际的过滤操作的方法，当客户请求访问与过滤器关联的URL时，Servlet容器先调用该方法。FilterChain参数用来访问后续的过滤器的doFilter()方法。
l destroy() Servlet容器在销毁过滤器实例前调用该方法，在这个方法中，可以释放过滤器占用的资源。
下面是一个过滤器的例子，它可以拒绝列在黑名单上的客户访问留言簿，而且能将服务器响应客户请求所花的时间写入日志：
//WEB-INF/classes/NoteFilter.class
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class NoteFilter implements Filter{
private FilterConfig config=null;
private String blackList=null;
public void init(FilterConfig config)throws ServletException{
this.config=config;
blackList=config.getInitParameter(“blacklist”);
}
public void destroy(){
config=null;
}
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException{
String userName=((HttpServletRequest)request).getParameter(“user_name”);
if(userName!=null)
userName=new String(userName.getBytes(“ISO-8859-1”),”GB2312”);
if(userName!=null && userName.indexOf(blackList)!=-1){
PrintWriter out=response.getWriter();
out.print(“<html><body>”);
out.print(“<h1>对不起，”+userName+”，你没有权限留言</h1>”);
out.print(“</body></html>”);
out.flush();
return;
}
long before=System.currentTimeMillis();
config.getServletContext().log(“NoteFilter:before call chain.doFilter()”);
chan.doFilter(request, response);
config.getServletContext().log(“NoteFilter:after call chain.doFilter()”);
logn after=System.currentTimeMillis();
String name=””;
if(request instanceof HttpServletRequest)
name=((HttpServletRequest)request).getRequestURL();
config.getServletContext().log(“NoteFilter:”+name+”:”+(after-before)+”ms”);
}
}
发布Servlet过滤器，必须在web.xml文件中加入<filter>和<filter-mapping>元素，如下：
<filter>
<filter-name>NoteFilter</filter>
<filter-class>NoteFilter</filter-class>
<init-param>
<param-name>blackList</param-name>
<param-value>捣蛋鬼</param-value>
</init-param>
<filter>
<filter-mapping>
<filter-name>NoteFilter</filter-name>
<url-pattern>/note</url-pattern>
</filter-mapping>
多个过滤器可以串连起来协同工作，Servlet容器将根据它们在web.xml中定义的先后顺序，依次调用它们的doFilter()方法。而这些过滤之间的关系不需要任何配置。
Listener的作用类似于load-on-startup的Servlet,在Web应用启动时被加载,在Web应用关闭时被销毁，Listener用来作为Web应用的后台服务，比load-on-startup的Servlet更早被加载到Servlet容器中。自定义的Listener类必须实现ServletContextListener接口，并实现该接口的两个方法：contextInitialized(ServletContextEvent)和contextDestroyed(ServletContextEvent)，例如：
public class GetConnListener implements ServletContextListener{
public void contextInitialized(ServletContextEvent sce){
try{
ServletContext application=sce.getServletContext();
String driver=application.getInitParameter("driver");
String url=application.getInitParameter("url");
String user=application.getInitParameter("user");
String password=application.getInitParameter("password");
Class.forName(driver);
Connection conn=DriverManager.getConnection(url, user, password);
application.setAttribute("conn", conn);
}catch(Exception e){
System.out.println("Listener中获取数据库连接出现异常:"+e.getMessage());
}
}
public void contextDestroyed(ServletContextEvent sce){
ServletContext application=sce.getServletContext();
Connection conn=(Connection)application.getAtrribute("conn");
if(conn!=null){
try{
conn.close();
conn=null;
}catch(Exception e){}
}
}
}
Listener配置：
<listener>
<listener-class>lee.GetConnListener</listener-class>
</listener>
自定义JSP标签库
实现自定义标签的处理类
JSP容器编译JSP网页时，遇到自定义标签，就会调用这个标签的处理类。标签处理类必须扩展自javax.servlet.jsp.TagSupport类或javax.servlet.jsp.BodyTagSupport类。
1、TagSupport类的主要方法如下：
l doStartTag JSP容器遇到自定义标签的起始标志时调用该方法。
l doEndTag JSP容器遇到自定义标签的结束标志时调用该方法。
l setValue(String k, Object v) 在标签处理类中设置key/value。
l getValue(String k) 在标签处理类中获得key对应的value。
l removeValue(String k) 在标签处理类中删除key/value。
l setPageContext(PageContext pc) 设置PageContext对象，由JSP容器在调用doStartTag或doEndTag方法之前调用。
l setParent(Tag t) 设置该标签的上层标签的处理类，由JSP容器在调用doStartTag或 doEndTag方法之前调用。
l getParent() 返回该标签的上层标签的处理类。
2、TagSupport类有两个重要属性：
l parent 该标签的上层标签的处理类。
l pageContext Web应用中的javax.servlet.jsp.PageContext对象，提供了保存和访问Web应用的共享数据方法：setAttribute(String name, Object value, int scope)和getAttribute(String name, int scope)。其中scope参数用来指定属性存在的范围，可选值有：PageContext.PAGE_SCOPE、PageContext.REQUEST_SCOPE、PageContext.SESSION_SCOPE和PageContext.APPLICATION_SCOPE。
注意：在TagSupport的构造函数中不能访问pageContext成员，因为此时JSP容器还没有调用setPageContext 方法对pageContext进行初始化。
3、处理标签的方法：
当JSP容器遇到自定义标签的起始标志时，就会调用该标签处理类的doStartTag()方法。doStartTag()方法返回一个整数值，用来决定程序的后续流程，有两个可选值：Tag.SKIP_BODY和Tag.EVAL_BODY_INCLUDE。Tag.SKIP_BODY表示标签之间的内容被忽略，例如：
<prefix:mytag>
Hello World!
</prefix:mytag>
如果这个标签的处理类的doStartTag()方法返回Tag.SKIP_BODY，则Hello World!字符串不会显示在网页上。Tag.EVAL_BODY_INCLUDE表示标签之间的内容会被处理。
当JSP容器遇到自定义标签的结束标志时，就会调用该标签处理类的doEndTag()方法。doEndTag()方法也返回一个整数值，表示程序的后续流程，也是有两个可选值：Tag.SKIP_PAGE和Tag.EVAL_PAGE。Tag.SKIP_PAGE表示立刻停止执行JSP页面，该标签的结束标志之后的所有页面内容全部会初忽略，任何已有的输出内容立刻返回到客户的浏览器上；Tag.EVAL_PAGE表示按正常的流程继续执行JSP页面的内容。
4、自定义标签的属性
例如：<prefix:mytag attribute1=”value1”>…</prefix:mytag>
那么在标签处理类中必须将这个属性作为类的成员变量，并且必须提供相应的getter和setter方法，例如：
private int attribute1;
public void setAttribute1(int value){ attribute1=value;}
public int getAttribute1(){return attribute1;}
以下是一个自定义标签<message>的处理类的例子：
// WEB-INF/classess/mypack/MessageTag.class
package mypack;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspTagException;
import javax.servlet.jsp.TagSupport;
import javax.servlet.http.HttpSession;
import java.util.Properties;
import java.io.*;
public class MessageTag extends TagSupport{
private String key=null;
public MessageTag(){}
public void setKey(String key){
this.key=key;
}
public String getKey(){
return key;
}
public int doEndTag() throws JspException{
try{
pageContext.getOut.print(key);
}catch(Exception e){
throw new JspTagException(e.getMessage());
}
return SkIP_BODY;
}
public void release(){
super.release();
}
}
创建标签库描述文件(Tag Library Descriptor, TLD)
TLD文件中的元素可分为3类：
l <taglib>元素用来设置标签库的相关信息，它有如下属性：
tlibversion 指定标签库的版本
jspversion 指定JSP的版本
shortname 指定标签库默认的前缀名(prefix)
uri 设置标签库的唯一访问标示符
info 标签库的说明信息
l <tag>元素用来定义一个标签，它的属性如下：
name 标签的名字
tagclass 标签的处理类
bodycontent 标签主体(body)的内容
info 标签的说明信息
说明：bodycontent属性有3个可选值：empty、JSP和tagdependent。empty表示标签没有主体，JSP表示标签的主体中可以加入JSP代码，tagdependent表示标签的主体的内容由标签的处理类自己去处理。
l <attribute>元素用来定义标签的属性，它有如下属性：
name 属性名
required 该属性是否必须，默认是false
rtexprvalue 该属性的值是否可能通过”<%=…%>”的方式获得，当设置为true时，该属性就可以采用如下的方式设置值：<% int num=1;%> <prefix:mytag attribute1=”<%=num%>”/>
以下是一个标签库描述文件的例子：
<!--WEB-INF/mytag.tld-->
<?xml version=”1.0” encoding=”ISO-8859-1”?>
<!DOCTYPE taglib PUBLIC “-//Sun Microsystems,Inc.//DTD JSP TagLibrary 1.1//EN”
“http://java.sun.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd”>
<taglib>
<tlibversion>1.0</tlibversion>
<jspversion>1.1</jspversion>
<shortname>mytaglib</shortname>
<uri>/mytaglib</uri>
<tag>
<name>message</name>
<tagclass>mypack.MessageTag</tagclass>
<bodycontent>empty</bodycontent>
<info>produce message by key</info>
<attribute>
<name>key</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
</tag>
</taglib>
在web.xml文件中加入标签库的定义
<taglib>
<!--标签库的唯一标示符，与标签库描述文件中的<uri>元素的内容相同，在JSP页面中，也要通过这个定义来使用标签库-->
<taglib-uri>/mytaglib</taglib-uri>
<!--指定标签库描述文件所在的位置-->
<taglib-location>/WEB-INF/mytaglib.tld</taglib-location>
</taglib>
在JSP页面中使用自定义的标签
例如：
<%@ taglib uri=”/mytaglib” prefix=”mm”%>
<html>
<body>
<mm:message key=”hello world!”/>
</body>
</html>
Java对于处理JSON数据的序列化与反序列化目前常用的类库有Gson、FastJSON、Jackson、jettison以及json-lib。在这里我们将对这些类库在json序列化与反序列化方面的性能进行测试对比。
个例测试，仅供参考。
测试环境如下：
电脑：cpu为I3-4160，Win7 64位系统
编译环境：jdk1.8.0_65，Myeclipse2014
各类库版本：gson-2.6.2、fastjson-1.2.8、jackson -2.7.2、jettison-1.3.7（2014年后无更新）、json-lib-2.4(2012年后停止更新)
序列化的简单对象：
publicclass User {
intid;
String name;
intage;
String address;
//get、set
}
测试结果：
序列化测试结果（Object->String），耗时单位均为ms
|
测试次数 类库 |
100 |
1K |
1W |
10W |
50W |
100W |
1000W |
|
gson |
8 |
25 |
63 |
230 |
680 |
1100 |
7790 |
|
fastjson |
85 |
100 |
155 |
200 |
270 |
350 |
1850 |
|
jackson |
35 |
48 |
80 |
150 |
255 |
360 |
2400 |
|
Json-lib |
75 |
130 |
280 |
910 |
2725 |
4900 |
42500 |
|
jettison |
70 |
85 |
110 |
210 |
400 |
590 |
4000 |
反序列化测试结果（String->Object），耗时单位均为ms
|
测试次数 类库 |
100 |
1K |
1W |
10W |
50W |
100W |
1000W |
|
gson |
9 |
21 |
60 |
195 |
570 |
950 |
7760 |
|
fastjson |
85 |
105 |
150 |
225 |
370 |
545 |
3800 |
|
jackson |
36 |
50 |
110 |
210 |
380 |
570 |
4460 |
|
Json-lib |
86 |
185 |
405 |
1180 |
2950 |
4850 |
38300 |
|
jettison |
6 |
20 |
50 |
230 |
460 |
710 |
4650 |
测试总结：
1、从测试结果可以看出gson在小于10w的数据量处理上，耗时相对较少，但是在数据越来越大的情况下耗时会明显的增长。
2、无论那种情况下，json-lib的耗时都是最多的，引用时还需要额外几个依赖包，且目前已经停止了更新，所以不推荐使用。
3、jackson在各阶段数据量都有很不错的性能，而fastjson在数据量较多的情况下也有很好性能。
4、jettison性能不错，但只提供json和其JSONObject对象相互转化的方法，转为自定义bean时需要再手动将JSONObject对象转为需要的bean。
结果码参照http协议状态码制定，下表状态码表示接口必定用到，其它状态码请参考标准HTTP状态码表。
| 状态码 | 状态消息 | 含义 |
| 200 | OK | 请求成功可按业务解析结果 |
| 400 | Bad request
（坏请求） |
请求的数据未按要求提供 |
| 401 | Unauthorized
（未授权） |
客户端未授权或授权无效 |
| 403 | Forbidden | 服务器已经理解请求，但是拒绝执行它。
此时需要根据错误码表查询具体的错误原因 |
| 404 | Not Found
（未找到） |
找不到资源 |
| 500 | Server Error
(服务器错误) |
服务器发生故障 |
| 503 | Service Unavailable
（服务器临时维护） |
服务器临时维护 |
当接口 HTTP Status 状态码响应为 403 时，表示当前请求的业务不能按要求完成，响应不能完成此请求的错误描述。
错误码查阅 “系统级错误编码表” 与 “业务级错误编码表”。
错误返回值格式： JSON
| {
"code" : "105", "message" : " IP requests out of rate limit" } |
系统级错误编码由 1 – 999 ，保留为通用级业务响应，不允许业务模块对其进行使用。
| 错误码 | 含义 |
| 100 | Too many pending tasks, system is busy
任务过多，系统繁忙 |
| 101 | Job expired
任务超时 |
| 102 | Illegal request
非法请求 |
| 103 | Request api not found
接口不存在 |
| 104 | HTTP method is not suported for this request
请求的HTTP METHOD不支持，是否选择了正确的POST/GET方式 |
| 105 | IP requests out of rate limit
IP请求频次超过上限 |
| 106 | User requests out of rate limit
用户对资源的请求频次超过上限 |
| … | |
| 999 |
业务级错误编码为 1000 - 9999 范围，其中前两位表示模块，后两位表示具体错误。
错误代码1001 的解释说明
| 10 | 01 |
| 服务模块代码 | 具体错误代码 |
模块
| 10 | 账号 |
| 11 | 订单 |
| 12 | 送货单 |
| 13 | 出库单 |
| 14 | 物流单 |
| 15 | 入库单 |
| 16 | 结算单 |
| 17 | 发票 |
| 错误码 | 含义 |
| 1000 | 账号问题，具体错误原因查阅message |
| 1001 | 账号被冻结 |
| 1100 | 订单问题，具体错误原因查阅message |
| 1101 | 订单不存在 |
| 1102 | 订单当前状态不允许进行此操作 |
| 1200 | 送货单问题，具体错误原因查阅message |
| 1300 | 出库单问题，具体错误原因查阅message |
| 1400 | 物流单问题，具体错误原因查阅message |
| 1500 | 入库单问题，具体错误原因查阅message |
| 1600 | 结算单问题，具体错误原因查阅message |
| 1700 | 发票问题，具体错误原因查阅message |
英文原文：https://blog.dumper.io/showdown-mysql-8-vs-postgresql-10/
中文原文：https://www.oschina.net/translate/showdown-mysql-8-vs-postgresql-10
.
与fdisk创建MBR分区一样，sgdisk是一个创建GPT分区的工具，了解GPT分区可参考The difference between booting MBR and GPT with GRUB。
# sgdisk -p /dev/sdb Disk /dev/sdb: 16780288 sectors, 8.0 GiB Logical sector size: 512 bytes Disk identifier (GUID): 4D5B29E8-6E0B-45DA-8E52-A21910E74479 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 16780254 Partitions will be aligned on 2048-sector boundaries Total free space is 4061 sectors (2.0 MiB) Number Start (sector) End (sector) Size Code Name 1 10487808 16780254 3.0 GiB FFFF ceph data 2 2048 10485760 5.0 GiB FFFF ceph journal
#/usr/sbin/sgdisk --info=1 /dev/sdb Partition GUID code: 89C57F98-2FE5-4DC0-89C1-F3AD0CEFF2BE (Unknown) Partition unique GUID: C8D04950-18E6-4102-A867-B874CF94EA74 First sector: 10487808 (at 5.0 GiB) Last sector: 16780254 (at 8.0 GiB) Partition size: 6292447 sectors (3.0 GiB) Attribute flags: 0000000000000000 Partition name: 'ceph data'
# sgdisk --zap-all --clear --mbrtogpt /dev/sdb GPT data structures destroyed! You may now partition the disk using fdisk or other utilities. The operation has completed successfully.
sgdisk
-n 创建一个分区， -n后的参数分别是： 分区号:起始地址:终止地址
分区号如果为0，代表使用第一个可用的分区号；
起始地址和终止地址可以为0，0代表第一个可用地址和最后一个可用地址；
起始地址和终止地址可以为+/-xxx，代表偏移量，+代表在起始地址后的xxx地址，-代表在终止地址前的xxx地址；
创建一个新分区，并指定类型为 Linux system
sgdisk -n 0:0:+20G -t 0:45b0969e-9b03-4f30-b4c6-b4b80ceff106 -p /dev/sde
创建分区2，扇区从2048到10485760，type code为8300。
# sgdisk -n 2:2048:10485760 -t 2:8300 -p /dev/sdb
Disk /dev/sdb: 16780288 sectors, 8.0 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): 5888A491-1245-4B40-8AEA-A6AEB2C302BB
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 16780254
Partitions will be aligned on 2048-sector boundaries
Total free space is 6296508 sectors (3.0 GiB)
Number Start (sector) End (sector) Size Code Name
2 2048 10485760 5.0 GiB 8300
Warning: The kernel is still using the old partition table.
The new table will be used at the next reboot.
The operation has completed successfully.
# sgdisk -n 1:2048 -t 1:8300 -p /dev/sdb
Disk /dev/sdb: 7813837232 sectors, 3.6 TiB
Logical sector size: 512 bytes
Disk identifier (GUID): 361860D7-33F5-45E6-9A86-406FE19B1C36
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 7813837198
Partitions will be aligned on 2048-sector boundaries
Total free space is 4294969310 sectors (2.0 TiB)
Number Start (sector) End (sector) Size Code Name
1 2048 3518869902 1.6 TiB 8300
The operation has completed successfully.
删除分区2。
# sgdisk --delete=2 /dev/sdb Warning: The kernel is still using the old partition table. The new table will be used at the next reboot. The operation has completed successfully.
| Option | Argument(s) | Purpose |
|---|---|---|
| -b or --backup | filename | Save a backup of the disk to the specified file. |
| -c or --change-name | partnum:name | Change the name of the specified partition. |
| -d or --delete | partnum | Delete the specified partition. |
| -E or --end-of-largest | none | Display the sector number at the end of the largest empty block of sectors on the disk. |
| -f or --first-in-largest | none | Display the sector number of the start of the largest empty block of sectors on the disk. |
| -F or --first-aligned-in-largest | none | Display the sector number of the first usable sector of the largest empty block of sectors on the disk, after partition alignment is considered. |
| -g or --mbrtogpt | none | Convert an MBR or BSD disklabel disk to GPT format. |
| -i or --info | partnum | Display detailed information on the specified partition. |
| -n or --new | partnum:start:end | Create a new partition, numbered partnum, starting at sector start and ending at sector end. |
| -o or --clear | none | Erase all GPT data structures and create a fresh GPT. |
| -p or --print | none | Display the current partition table. |
| -P or --pretend | none | Perform actions only on in-memory representation; don't save changes to disk. |
| -t or --typecode | partnum:hexcode | Change a partition's GUID type code to the one specified by hexcode. Note that hexcode is a gdisk/sgdisk internal two-byte hexadecimal code. You can obtain a list of codes with the -L option. |
| -v or --verify | none | Verify the integrity of the partition table and report the results. |
| -V or --version | none | Display the version number |
| -z or --zap | none | Zero out all GPT and MBR data structures. Use this option if you want to completely erase the GPT data structures so that the disk can be used as an MBR disk without concern that it might contain stray GPT data. |
Additional options are documented in the sgdisk man page. The -E, -f, and -F options require a bit of elaboration. These options all work by finding the largest contiguous area of unallocated space on the disk and then returning the numbers of the final (-E), first (-f), and first usable (-F), free sectors in that area. The idea is to facilitate automated creation of partitions by locating where they might reasonably reside, even if there are short gaps between existing partitions. Such gaps can be created by MBR-to-GPT conversions, by sector alignment, or by some OSes' partitioning tools (Apple's Disk Utility creates 128 MiB gaps between partitions, for instance.) If you need to know where a partition will actually begin if you create it with the current partition alignment, use -F; but if you need to know where a partition could begin if alignment were set to 1 sector, use -f.
Some options take a single value as an argument, such as a filename or a partition number (partnum in the preceding table). Other options require compound arguments, with parts separated by colons (:).
Option order is important: Actions are performed in the order in which they are specified on the command line. This can have implications for the validity of certain commands. For instance, changing a partition's name and then deleting it is legal, but deleting a partition and then changing its name is not legal. sgdisk will refuse to save changes if you try the latter—but you shouldn't count on sgdisk catching such egregious errors.
# sgdisk -p /dev/sdc *************************************************************** Found invalid GPT and valid MBR; converting MBR to GPT format. *************************************************************** Disk /dev/sdc: 15654912 sectors, 7.5 GiB Logical sector size: 512 bytes Disk identifier (GUID): 82DCA0EC-C906-0169-D834-38EAB3C3E012 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 15654878 Partitions will be aligned on 2-sector boundaries Total free space is 3999 sectors (2.0 MiB) Number Start (sector) End (sector) Size Code Name 1 62 15650907 7.5 GiB 0700 Linux/Windows data
You must know the name of the device file that's used to access the disk. For Linux, this file is likely to take the form /dev/sdx or /dev/hdx, where x is a letter. In Mac OS X, the device filename takes the form /dev/disky, where y is a number from 0 up.
sgdisk automatically converts the MBR to GPT form and displays the converted partition. Because the -p option is informational only, changes aren't saved back. The disk could have been converted to GPT by adding the -g option.
Suppose you want to replace the one existing partition with three new partitions: A 1 GiB partition for Linux, a 3 GiB shared FAT partition, and a 3.5 GiB FreeBSD partition. You might begin by deleting the existing partition and creating the Linux partition:
# sgdisk -d 1 -n 1:34:2097151 -g /dev/sdc *************************************************************** Found invalid GPT and valid MBR; converting MBR to GPT format. *************************************************************** The operation has completed successfully.
The -g option is necessary to save the changes, since the disk had an MBR configuration initially. At this point, it's GPT, but the program didn't print the partition table, since no -p option was included. The default type for a new partition varies from one platform to another. In Linux, it's 8300 (Linux filesystem), so the previous example didn't need to change the partition type. The next one, however, does; it uses the -t option to set the type code to 0700 (Microsoft basic data) for one partition and A503 (FreeBSD UFS) for the other:
# sgdisk -n 2:2097152:8388607 -n 3:8388608:15654878 -t 2:0700 -t 3:a503 -p /dev/sdc Disk /dev/sdc: 15654912 sectors, 7.5 GiB Logical sector size: 512 bytes Disk identifier (GUID): 8C5B1844-CEAE-2370-00BD-D0E47E3C9900 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 15654878 Partitions will be aligned on 2-sector boundaries Total free space is 0 sectors (0 bytes) Number Start (sector) End (sector) Size Code Name 1 34 2097151 1024.0 MiB 8300 2 2097152 8388607 3.0 GiB 0700 3 8388608 15654878 3.5 GiB A503 The operation has completed successfully.
Instead of specifying unwieldy sector numbers, you can specify partition start points and sizes using abbreviations, such as +4G as an end point to make a 4 GiB partition. Sector numbers may be rounded to multiples of 2048 (1 MiB), which is necessary to optimize performance on some types of disks.
If you want to add names to the partitions to help identify them, you can use the -c option:
# sgdisk -c 1:"Linux data" -c 2:"Shared FAT" -c 3:FreeBSD /dev/sdc The operation has completed successfully. # sudo sgdisk -p /dev/sdc Disk /dev/sdc: 15654912 sectors, 7.5 GiB Logical sector size: 512 bytes Disk identifier (GUID): 8C5B1844-CEAE-2370-00BD-D0E47E3C9900 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 15654878 Partitions will be aligned on 2-sector boundaries Total free space is 0 sectors (0 bytes) Number Start (sector) End (sector) Size Code Name 1 34 2097151 1024.0 MiB 0700 Linux data 2 2097152 8388607 3.0 GiB 0700 Shared FAT 3 8388608 15654878 3.5 GiB A503 FreeBSD
This example illustrates the fact that quotes are required around partition names if they contain spaces, but quotes need not be used for single-word partition names.
#!/bin/bash sgdisk -og $1 sgdisk -n 1:2048:4095 -c 1:"BIOS Boot Partition" -t 1:ef02 $1 sgdisk -n 2:4096:413695 -c 2:"EFI System Partition" -t 2:ef00 $1 sgdisk -n 3:413696:823295 -c 3:"Linux /boot" -t 3:8300 $1 ENDSECTOR=`sgdisk -E $1` sgdisk -n 4:823296:$ENDSECTOR -c 4:"Linux LVM" -t 4:8e00 $1 sgdisk -p $1
This script is, of course, fairly simple. Despite this, it illustrates one important feature: By assigning the output of sgdisk -E (containing the number of the last sector in the largest free block) to a variable and then using that value later, the script adapts to disks of different sizes. (A better solution in this case is to use a sector value of 0, which refers to the default value, which is the end of the free space when creating a partition; but I wanted to illustrate this assignment method.) A more sophisticated script could use the output of sgdisk -F, as well, and perform arithmetic—say, splitting the available free space in some ratio between two or more new partitions. The output of the -p, -i, or other options could also be used, although more processing would be required to do so. This approach could be used in a disk-cloning script; partitions on the source disk could be re-created on the target disk, perhaps adapting one or more partitions' sizes as required.
Some caveats are in order. The most important is that error conditions and even varying disk contents can cause unpredictable behavior. For instance, the output of sgdisk varies depending on whether the disk contains an MBR, a GPT, or some other type of partition table. A command such as the assignment to the ENDSECTOR variable in the preceding script could fail if sgdisk encounters a type of disk you don't anticipate. Such a problem is only likely to affect the preceding script if the partition table is badly corrupt; however, if the assignment to ENDSECTOR had been the first line of the script, the script would fail on MBR disks. You should be sure to test your script thoroughly to prevent such problems.
Another issue is that each call to sgdisk takes a certain amount of time. This time increases when the program must write its changes to disk. The preceding script takes about six seconds to execute on a USB flash drive. This time could be reduced by merging the options into fewer calls to sgdisk—perhaps one for clearing the partition table and creating the first three partitions, a second for finding the end sector, and a final one for creating the LVM partition and displaying the final partition table. Making this change reduces the run time to about two seconds on my system. Of course, the USB flash drive I used for testing this effect is slow compared to a hard disk; but if you write a script with many calls to sgdisk and you find it's sluggish, consolidating those calls may make a difference.
Unlike GNU Parted and related tools, neither GPT fdisk program creates filesystems. Thus, if you want your script to take care of this task, you'll have to use a call to mkfs or a similar utility to do the job. Note, however, that the Linux kernel sometimes continues to use the old partition table after you've made changes. You must remove and re-install a removable disk or reboot the computer before the computer uses the new partition table. Thus, you should be cautious about moving from partition creation to filesystem creation in a script. Such inconsistencies are most likely to occur on disks with mounted partitions, but I've seen them even on disks with no mounted partitions from time to time.
Partition type (type L to list all types): L
| 1 | EFI System | C12A7328-F81F-11D2-BA4B-00A0C93EC93B |
| 2 | MBR partition scheme | 024DEE41-33E7-11D3-9D69-0008C781F39F |
| 3 | Intel Fast Flash | D3BFE2DE-3DAF-11DF-BA40-E3A556D89593 |
| 4 | BIOS boot | 21686148-6449-6E6F-744E-656564454649 |
| 5 | Sony boot partition | F4019732-066E-4E12-8273-346C5641494F |
| 6 | Lenovo boot partition | BFBFAFE7-A34F-448A-9A5B-6213EB736C22 |
| 7 | PowerPC PReP boot | 9E1A2D38-C612-4316-AA26-8B49521E5A8B |
| 8 | ONIE boot | 7412F7D5-A156-4B13-81DC-867174929325 |
| 9 | ONIE config | D4E6E2CD-4469-46F3-B5CB-1BFF57AFC149 |
| 10 | Microsoft reserved | E3C9E316-0B5C-4DB8-817D-F92DF00215AE |
| 11 | Microsoft basic data | EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 |
| 12 | Microsoft LDM metadata | 5808C8AA-7E8F-42E0-85D2-E1E90434CFB3 |
| 13 | Microsoft LDM data | AF9B60A0-1431-4F62-BC68-3311714A69AD |
| 14 | Windows recovery environment | DE94BBA4-06D1-4D40-A16A-BFD50179D6AC |
| 15 | IBM General Parallel Fs | 37AFFC90-EF7D-4E96-91C3-2D7AE055B174 |
| 16 | Microsoft Storage Spaces | E75CAF8F-F680-4CEE-AFA3-B001E56EFC2D |
| 17 | HP-UX data | 75894C1E-3AEB-11D3-B7C1-7B03A0000000 |
| 18 | HP-UX service | E2A1E728-32E3-11D6-A682-7B03A0000000 |
| 19 | Linux swap | 0657FD6D-A4AB-43C4-84E5-0933C84B4F4F |
| 20 | Linux filesystem | 0FC63DAF-8483-4772-8E79-3D69D8477DE4 |
| 21 | Linux server data | 3B8F8425-20E0-4F3B-907F-1A25A76F98E8 |
| 22 | Linux root (x86) | 44479540-F297-41B2-9AF7-D131D5F0458A |
| 23 | Linux root (ARM) | 69DAD710-2CE4-4E3C-B16C-21A1D49ABED3 |
| 24 | Linux root (x86-64) | 4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709 |
| 25 | Linux root (ARM-64) | B921B045-1DF0-41C3-AF44-4C6F280D3FAE |
| 26 | Linux root (IA-64) | 993D8D3D-F80E-4225-855A-9DAF8ED7EA97 |
| 27 | Linux reserved | 8DA63339-0007-60C0-C436-083AC8230908 |
| 28 | Linux home | 933AC7E1-2EB4-4F13-B844-0E14E2AEF915 |
| 29 | Linux RAID | A19D880F-05FC-4D3B-A006-743F0F84911E |
| 30 | Linux extended boot | BC13C2FF-59E6-4262-A352-B275FD6F7172 |
| 31 | Linux LVM | E6D6D379-F507-44C2-A23C-238F2A3DF928 |
| 32 | FreeBSD data | 516E7CB4-6ECF-11D6-8FF8-00022D09712B |
| 33 | FreeBSD boot | 83BD6B9D-7F41-11DC-BE0B-001560B84F0F |
| 34 | FreeBSD swap | 516E7CB5-6ECF-11D6-8FF8-00022D09712B |
| 35 | FreeBSD UFS | 516E7CB6-6ECF-11D6-8FF8-00022D09712B |
| 36 | FreeBSD ZFS | 516E7CBA-6ECF-11D6-8FF8-00022D09712B |
| 37 | FreeBSD Vinum | 516E7CB8-6ECF-11D6-8FF8-00022D09712B |
| 38 | Apple HFS/HFS+ | 48465300-0000-11AA-AA11-00306543ECAC |
| 39 | Apple UFS | 55465300-0000-11AA-AA11-00306543ECAC |
| 40 | Apple RAID | 52414944-0000-11AA-AA11-00306543ECAC |
| 41 | Apple RAID offline | 52414944-5F4F-11AA-AA11-00306543ECAC |
| 42 | Apple boot | 426F6F74-0000-11AA-AA11-00306543ECAC |
| 43 | Apple label | 4C616265-6C00-11AA-AA11-00306543ECAC |
| 44 | Apple TV recovery | 5265636F-7665-11AA-AA11-00306543ECAC |
| 45 | Apple Core storage | 53746F72-6167-11AA-AA11-00306543ECAC |
| 46 | Solaris boot | 6A82CB45-1DD2-11B2-99A6-080020736631 |
| 47 | Solaris root | 6A85CF4D-1DD2-11B2-99A6-080020736631 |
| 48 | Solaris /usr & Apple ZFS | 6A898CC3-1DD2-11B2-99A6-080020736631 |
| 49 | Solaris swap | 6A87C46F-1DD2-11B2-99A6-080020736631 |
| 50 | Solaris backup | 6A8B642B-1DD2-11B2-99A6-080020736631 |
| 51 | Solaris /var | 6A8EF2E9-1DD2-11B2-99A6-080020736631 |
| 52 | Solaris /home | 6A90BA39-1DD2-11B2-99A6-080020736631 |
| 53 | Solaris alternate sector | 6A9283A5-1DD2-11B2-99A6-080020736631 |
| 54 | Solaris reserved 1 | 6A945A3B-1DD2-11B2-99A6-080020736631 |
| 55 | Solaris reserved 2 | 6A9630D1-1DD2-11B2-99A6-080020736631 |
| 56 | Solaris reserved 3 | 6A980767-1DD2-11B2-99A6-080020736631 |
| 57 | Solaris reserved 4 | 6A96237F-1DD2-11B2-99A6-080020736631 |
| 58 | Solaris reserved 5 | 6A8D2AC7-1DD2-11B2-99A6-080020736631 |
| 59 | NetBSD swap | 49F48D32-B10E-11DC-B99B-0019D1879648 |
| 60 | NetBSD FFS | 49F48D5A-B10E-11DC-B99B-0019D1879648 |
| 61 | NetBSD LFS | 49F48D82-B10E-11DC-B99B-0019D1879648 |
| 62 | NetBSD concatenated | 2DB519C4-B10E-11DC-B99B-0019D1879648 |
| 63 | NetBSD encrypted | 2DB519EC-B10E-11DC-B99B-0019D1879648 |
| 64 | NetBSD RAID | 49F48DAA-B10E-11DC-B99B-0019D1879648 |
| 65 | ChromeOS kernel | FE3A2A5D-4F32-41A7-B725-ACCC3285A309 |
| 66 | ChromeOS root fs | 3CB8E202-3B7E-47DD-8A3C-7FF2A13CFCEC |
| 67 | ChromeOS reserved | 2E0A753D-9E48-43B0-8337-B15192CB1B5E |
| 68 | MidnightBSD data | 85D5E45A-237C-11E1-B4B3-E89A8F7FC3A7 |
| 69 | MidnightBSD boot | 85D5E45E-237C-11E1-B4B3-E89A8F7FC3A7 |
| 70 | MidnightBSD swap | 85D5E45B-237C-11E1-B4B3-E89A8F7FC3A7 |
| 71 | MidnightBSD UFS | 0394EF8B-237E-11E1-B4B3-E89A8F7FC3A7 |
| 72 | MidnightBSD ZFS | 85D5E45D-237C-11E1-B4B3-E89A8F7FC3A7 |
| 73 | MidnightBSD Vinum | 85D5E45C-237C-11E1-B4B3-E89A8F7FC3A7 |
| 74 | Ceph Journal | 45B0969E-9B03-4F30-B4C6-B4B80CEFF106 |
| 75 | Ceph Encrypted Journal | 45B0969E-9B03-4F30-B4C6-5EC00CEFF106 |
| 76 | Ceph OSD | 4FBD7E29-9D25-41B8-AFD0-062C0CEFF05D |
| 77 | Ceph crypt OSD | 4FBD7E29-9D25-41B8-AFD0-5EC00CEFF05D |
| 78 | Ceph disk in creation | 89C57F98-2FE5-4DC0-89C1-F3AD0CEFF2BE |
| 79 | Ceph crypt disk in creation | 89C57F98-2FE5-4DC0-89C1-5EC00CEFF2BE |
| 80 | OpenBSD data | 824CC7A0-36A8-11E3-890A-952519AD3F61 |
| 81 | QNX6 file system | CEF5A9AD-73BC-4601-89F3-CDEEEEE321A1 |
| 82 | Plan 9 partition | C91818F9-8025-47AF-89D2-F030D7000C2C |
[root@node103 ~]# sgdisk -L
| 0700 Microsoft basic data
4200 Windows LDM data 7f00 ChromeOS kernel 8200 Linux swap 8e00 Linux LVM a502 FreeBSD swap a505 FreeBSD Vinum/RAID a582 Midnight BSD swap a585 Midnight BSD Vinum a902 NetBSD FFS a905 NetBSD encrypted af00 Apple HFS/HFS+ af03 Apple label be00 Solaris boot bf02 Solaris swap bf05 Solaris /home bf08 Solaris Reserved 2 bf0b Solaris Reserved 5 ed00 Sony system partitio ef02 BIOS boot partition fc00 VMWare kcore crash p |
0c01 Microsoft reserved
4201 Windows LDM metadata 7f01 ChromeOS root 8300 Linux filesystem a500 FreeBSD disklabel a503 FreeBSD UFS a580 Midnight BSD data a583 Midnight BSD UFS a800 Apple UFS a903 NetBSD LFS a906 NetBSD RAID af01 Apple RAID af04 AppleTV recovery bf00 Solaris root bf03 Solaris backup bf06 Solaris alternate se bf09 Solaris Reserved 3 c001 HP-UX data ef00 EFI System fb00 VMWare VMFS fd00 Linux RAID |
2700 Windows RE
7501 IBM GPFS 7f02 ChromeOS reserved 8301 Linux reserved a501 FreeBSD boot a504 FreeBSD ZFS a581 Midnight BSD boot a584 Midnight BSD ZFS a901 NetBSD swap a904 NetBSD concatenated ab00 Apple boot af02 Apple RAID offline af05 Apple Core Storage bf01 Solaris /usr & Mac Z bf04 Solaris /var bf07 Solaris Reserved 1 bf0a Solaris Reserved 4 c002 HP-UX service ef01 MBR partition scheme fb01 VMWare reserved
|
| Operating system | Partition type | Globally unique identifier (GUID)[d] |
|---|---|---|
| (None) | Unused entry | 00000000-0000-0000-0000-000000000000 |
| MBR partition scheme | 024DEE41-33E7-11D3-9D69-0008C781F39F | |
| EFI System partition | C12A7328-F81F-11D2-BA4B-00A0C93EC93B | |
| BIOS boot partition[e] | 21686148-6449-6E6F-744E-656564454649 | |
| Intel Fast Flash (iFFS) partition (for Intel Rapid Start technology)[29][30] | D3BFE2DE-3DAF-11DF-BA40-E3A556D89593 | |
| Sony boot partition[f] | F4019732-066E-4E12-8273-346C5641494F | |
| Lenovo boot partition[f] | BFBFAFE7-A34F-448A-9A5B-6213EB736C22 | |
| Windows | Microsoft Reserved Partition (MSR) | E3C9E316-0B5C-4DB8-817D-F92DF00215AE |
| Basic data partition[g] | EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 | |
| Logical Disk Manager (LDM) metadata partition | 5808C8AA-7E8F-42E0-85D2-E1E90434CFB3 | |
| Logical Disk Manager data partition | AF9B60A0-1431-4F62-BC68-3311714A69AD | |
| Windows Recovery Environment | DE94BBA4-06D1-4D40-A16A-BFD50179D6AC | |
| IBM General Parallel File System (GPFS) partition | 37AFFC90-EF7D-4E96-91C3-2D7AE055B174 | |
| Storage Spaces partition | E75CAF8F-F680-4CEE-AFA3-B001E56EFC2D | |
| HP-UX | Data partition | 75894C1E-3AEB-11D3-B7C1-7B03A0000000 |
| Service Partition | E2A1E728-32E3-11D6-A682-7B03A0000000 | |
| Linux | Linux filesystem data[g] | 0FC63DAF-8483-4772-8E79-3D69D8477DE4 |
| RAID partition | A19D880F-05FC-4D3B-A006-743F0F84911E | |
| Root partition (x86)[33] | 44479540-F297-41B2-9AF7-D131D5F0458A | |
| Root partition (x86-64)[33] | 4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709 | |
| Root partition (32-bit ARM)[33] | 69DAD710-2CE4-4E3C-B16C-21A1D49ABED3 | |
| Root partition (64-bit ARM/AArch64)[33] | B921B045-1DF0-41C3-AF44-4C6F280D3FAE | |
| Swap partition | 0657FD6D-A4AB-43C4-84E5-0933C84B4F4F | |
| Logical Volume Manager (LVM) partition | E6D6D379-F507-44C2-A23C-238F2A3DF928 | |
| /home partition[33] | 933AC7E1-2EB4-4F13-B844-0E14E2AEF915 | |
| /srv (server data) partition[33] | 3B8F8425-20E0-4F3B-907F-1A25A76F98E8 | |
| Plain dm-crypt partition[34][35][36] | 7FFEC5C9-2D00-49B7-8941-3EA10A5586B7 | |
| LUKS partition[34][35][36][37] | CA7D7CCB-63ED-4C53-861C-1742536059CC | |
| Reserved | 8DA63339-0007-60C0-C436-083AC8230908 | |
| FreeBSD | Boot partition | 83BD6B9D-7F41-11DC-BE0B-001560B84F0F |
| Data partition | 516E7CB4-6ECF-11D6-8FF8-00022D09712B | |
| Swap partition | 516E7CB5-6ECF-11D6-8FF8-00022D09712B | |
| Unix File System (UFS) partition | 516E7CB6-6ECF-11D6-8FF8-00022D09712B | |
| Vinum volume manager partition | 516E7CB8-6ECF-11D6-8FF8-00022D09712B | |
| ZFS partition | 516E7CBA-6ECF-11D6-8FF8-00022D09712B | |
| macOS Darwin |
Hierarchical File System Plus (HFS+) partition | 48465300-0000-11AA-AA11-00306543ECAC |
| Apple APFS | 7C3457EF-0000-11AA-AA11-00306543ECAC | |
| Apple UFS container | 55465300-0000-11AA-AA11-00306543ECAC | |
| ZFS[h] | 6A898CC3-1DD2-11B2-99A6-080020736631 | |
| Apple RAID partition | 52414944-0000-11AA-AA11-00306543ECAC | |
| Apple RAID partition, offline | 52414944-5F4F-11AA-AA11-00306543ECAC | |
| Apple Boot partition (Recovery HD) | 426F6F74-0000-11AA-AA11-00306543ECAC | |
| Apple Label | 4C616265-6C00-11AA-AA11-00306543ECAC | |
| Apple TV Recovery partition | 5265636F-7665-11AA-AA11-00306543ECAC | |
| Apple Core Storage (i.e. Lion FileVault) partition | 53746F72-6167-11AA-AA11-00306543ECAC | |
| SoftRAID_Status | B6FA30DA-92D2-4A9A-96F1-871EC6486200 | |
| SoftRAID_Scratch | 2E313465-19B9-463F-8126-8A7993773801 | |
| SoftRAID_Volume | FA709C7E-65B1-4593-BFD5-E71D61DE9B02 | |
| SoftRAID_Cache | BBBA6DF5-F46F-4A89-8F59-8765B2727503 | |
| Solaris illumos |
Boot partition | 6A82CB45-1DD2-11B2-99A6-080020736631 |
| Root partition | 6A85CF4D-1DD2-11B2-99A6-080020736631 | |
| Swap partition | 6A87C46F-1DD2-11B2-99A6-080020736631 | |
| Backup partition | 6A8B642B-1DD2-11B2-99A6-080020736631 | |
| /usr partition[h] | 6A898CC3-1DD2-11B2-99A6-080020736631 | |
| /var partition | 6A8EF2E9-1DD2-11B2-99A6-080020736631 | |
| /home partition | 6A90BA39-1DD2-11B2-99A6-080020736631 | |
| Alternate sector | 6A9283A5-1DD2-11B2-99A6-080020736631 | |
| Reserved partition | 6A945A3B-1DD2-11B2-99A6-080020736631 | |
| 6A9630D1-1DD2-11B2-99A6-080020736631 | ||
| 6A980767-1DD2-11B2-99A6-080020736631 | ||
| 6A96237F-1DD2-11B2-99A6-080020736631 | ||
| 6A8D2AC7-1DD2-11B2-99A6-080020736631 | ||
| NetBSD[38][i] | Swap partition | 49F48D32-B10E-11DC-B99B-0019D1879648 |
| FFS partition | 49F48D5A-B10E-11DC-B99B-0019D1879648 | |
| LFS partition | 49F48D82-B10E-11DC-B99B-0019D1879648 | |
| RAID partition | 49F48DAA-B10E-11DC-B99B-0019D1879648 | |
| Concatenated partition | 2DB519C4-B10F-11DC-B99B-0019D1879648 | |
| Encrypted partition | 2DB519EC-B10F-11DC-B99B-0019D1879648 | |
| Chrome OS[39] | Chrome OS kernel | FE3A2A5D-4F32-41A7-B725-ACCC3285A309 |
| Chrome OS rootfs | 3CB8E202-3B7E-47DD-8A3C-7FF2A13CFCEC | |
| Chrome OS future use | 2E0A753D-9E48-43B0-8337-B15192CB1B5E | |
| Haiku[40] | Haiku BFS | 42465331-3BA3-10F1-802A-4861696B7521 |
| MidnightBSD[41][i] | Boot partition | 85D5E45E-237C-11E1-B4B3-E89A8F7FC3A7 |
| Data partition | 85D5E45A-237C-11E1-B4B3-E89A8F7FC3A7 | |
| Swap partition | 85D5E45B-237C-11E1-B4B3-E89A8F7FC3A7 | |
| Unix File System (UFS) partition | 0394EF8B-237E-11E1-B4B3-E89A8F7FC3A7 | |
| Vinum volume manager partition | 85D5E45C-237C-11E1-B4B3-E89A8F7FC3A7 | |
| ZFS partition | 85D5E45D-237C-11E1-B4B3-E89A8F7FC3A7 | |
| Ceph[j] | Journal | 45B0969E-9B03-4F30-B4C6-B4B80CEFF106 |
| dm-crypt journal | 45B0969E-9B03-4F30-B4C6-5EC00CEFF106 | |
| OSD | 4FBD7E29-9D25-41B8-AFD0-062C0CEFF05D | |
| dm-crypt OSD | 4FBD7E29-9D25-41B8-AFD0-5EC00CEFF05D | |
| Disk in creation | 89C57F98-2FE5-4DC0-89C1-F3AD0CEFF2BE | |
| dm-crypt disk in creation | 89C57F98-2FE5-4DC0-89C1-5EC00CEFF2BE | |
| Block | CAFECAFE-9B03-4F30-B4C6-B4B80CEFF106 | |
| Block DB | 30CD0809-C2B2-499C-8879-2D6B78529876 | |
| Block write-ahead log | 5CE17FCE-4087-4169-B7FF-056CC58473F9 | |
| Lockbox for dm-crypt keys | FB3AABF9-D25F-47CC-BF5E-721D1816496B | |
| Multipath OSD | 4FBD7E29-8AE0-4982-BF9D-5A8D867AF560 | |
| Multipath journal | 45B0969E-8AE0-4982-BF9D-5A8D867AF560 | |
| Multipath block | CAFECAFE-8AE0-4982-BF9D-5A8D867AF560 | |
| Multipath block | 7F4A666A-16F3-47A2-8445-152EF4D03F6C | |
| Multipath block DB | EC6D6385-E346-45DC-BE91-DA2A7C8B3261 | |
| Multipath block write-ahead log | 01B41E1B-002A-453C-9F17-88793989FF8F | |
| dm-crypt block | CAFECAFE-9B03-4F30-B4C6-5EC00CEFF106 | |
| dm-crypt block DB | 93B0052D-02D9-4D8A-A43B-33A3EE4DFBC3 | |
| dm-crypt block write-ahead log | 306E8683-4FE2-4330-B7C0-00A917C16966 | |
| dm-crypt LUKS journal | 45B0969E-9B03-4F30-B4C6-35865CEFF106 | |
| dm-crypt LUKS block | CAFECAFE-9B03-4F30-B4C6-35865CEFF106 | |
| dm-crypt LUKS block DB | 166418DA-C469-4022-ADF4-B30AFD37F176 | |
| dm-crypt LUKS block write-ahead log | 86A32090-3647-40B9-BBBD-38D8C573AA86 | |
| dm-crypt LUKS OSD | 4FBD7E29-9D25-41B8-AFD0-35865CEFF05D | |
| OpenBSD | Data partition | 824CC7A0-36A8-11E3-890A-952519AD3F61 |
| QNX | Power-safe (QNX6) file system[43] | CEF5A9AD-73BC-4601-89F3-CDEEEEE321A1 |
| Plan 9 | Plan 9 partition | C91818F9-8025-47AF-89D2-F030D7000C2C |
| VMware ESX | vmkcore (coredump partition) | 9D275380-40AD-11DB-BF97-000C2911D1B8 |
| VMFS filesystem partition | AA31E02A-400F-11DB-9590-000C2911D1B8 | |
| VMware Reserved | 9198EFFC-31C0-11DB-8F78-000C2911D1B8 | |
| Android-IA[44][45][46][47] | Bootloader | 2568845D-2332-4675-BC39-8FA5A4748D15 |
| Bootloader2 | 114EAFFE-1552-4022-B26E-9B053604CF84 | |
| Boot | 49A4D17F-93A3-45C1-A0DE-F50B2EBE2599 | |
| Recovery | 4177C722-9E92-4AAB-8644-43502BFD5506 | |
| Misc | EF32A33B-A409-486C-9141-9FFB711F6266 | |
| Metadata | 20AC26BE-20B7-11E3-84C5-6CFDB94711E9 | |
| System | 38F428E6-D326-425D-9140-6E0EA133647C | |
| Cache | A893EF21-E428-470A-9E55-0668FD91A2D9 | |
| Data | DC76DDA9-5AC1-491C-AF42-A82591580C0D | |
| Persistent | EBC597D0-2053-4B15-8B64-E0AAC75F4DB1 | |
| Vendor | C5A0AEEC-13EA-11E5-A1B1-001E67CA0C3C | |
| Config | BD59408B-4514-490D-BF12-9878D963F378 | |
| Factory | 8F68CC74-C5E5-48DA-BE91-A0C8C15E9C80 | |
| Factory (alt)[48] | 9FDAA6EF-4B3F-40D2-BA8D-BFF16BFB887B | |
| Fastboot / Tertiary[49][50] | 767941D0-2085-11E3-AD3B-6CFDB94711E9 | |
| OEM | AC6D7924-EB71-4DF8-B48D-E267B27148FF | |
| Android 6.0+ ARM | Android Meta | 19A710A2-B3CA-11E4-B026-10604B889DCF |
| Android EXT | 193D1EA4-B3CA-11E4-B075-10604B889DCF | |
| Open Network Install Environment (ONIE) | Boot | 7412F7D5-A156-4B13-81DC-867174929325 |
| Config | D4E6E2CD-4469-46F3-B5CB-1BFF57AFC149 | |
| PowerPC | PReP boot | 9E1A2D38-C612-4316-AA26-8B49521E5A8B |
| freedesktop.org OSes (Linux, etc.) | Shared boot loader configuration[51] | BC13C2FF-59E6-4262-A352-B275FD6F7172 |
| Atari TOS | Basic data partition (GEM, BGM, F32) | 734E5AFE-F61A-11E6-BC64-92361F002671 |
linux 新版本硬盘顺序会发生变化，因此改为使用UUID做为分区标识。
如： sda/sdb/sdc， 增加一块硬盘后原sdb可能会变成sde
一、uuid 与挂载点
1、使用blkid命令获取UUID
#blkid
/dev/sda1: SEC_TYPE="msdos" UUID="F159-EA55" TYPE="vfat" PARTLABEL="EFI System Partition" PARTUUID="ed7d2e13-8197-4226-8fdc-47d4aa64aebb"
/dev/sda2: LABEL="boot" UUID="f7755604-99f2-4d94-ab1a-47b14def7e26" TYPE="xfs" PARTUUID="627c028f-bf10-4705-b465-d5118d8ee67d"
/dev/sda3: UUID="Bs0vJv-cena-E9eO-2WcM-iJNQ-26Mr-fGG1pr" TYPE="LVM2_member" PARTUUID="18c50ff9-0e0d-40ac-8e2a-4f7f768347ed"
/dev/mapper/cl-root: UUID="b2f57437-ba99-4a2d-9c82-a41037aa0e38" TYPE="xfs"
/dev/mapper/cl-swap: UUID="2930b30d-3039-442d-a210-da1d7775652e" TYPE="swap"
/dev/mapper/cl-data: LABEL="data" UUID="cfc65b4e-0ca4-4b48-934e-5f668a4fb3b5" TYPE="xfs"
查看/dev目录获取UUID
#ll /dev/disk/by-uuid/
lrwxrwxrwx 1 root root 10 11月 25 19:56 2930b30d-3039-442d-a210-da1d7775652e -> ../../dm-1
lrwxrwxrwx 1 root root 10 11月 25 19:56 b2f57437-ba99-4a2d-9c82-a41037aa0e38 -> ../../dm-0
lrwxrwxrwx 1 root root 10 11月 25 19:56 cfc65b4e-0ca4-4b48-934e-5f668a4fb3b5 -> ../../dm-2
lrwxrwxrwx 1 root root 10 11月 25 19:56 F159-EA55 -> ../../sda1
lrwxrwxrwx 1 root root 10 11月 25 19:56 f7755604-99f2-4d94-ab1a-47b14def7e26 -> ../../sda2
修改/etc/fstab文件，使用uuid
# cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Mon Sep 8 16:38:29 2014
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/cl-root / xfs defaults 1 1
UUID=f7755604-99f2-4d94-ab1a-47b14def7e26 /boot xfs defaults 1 2
UUID=F159-EA55 /boot/efi vfat umask=0077,shortname=winnt 0 0
/dev/mapper/cl-data /data xfs defaults,noatime,nobarrier 1 2
/dev/mapper/cl-swap swap swap defaults 0 0
...
计算引擎层
Hadoop生态和其他生态最大的不同之一就是“单一平台多种应用”的理念了。传的数据库底层只有一个引擎，只处理关系型应用，所以是“单一平台单一应用”；而NoSQL市场有上百个NoSQL软件，每一个都针对不同的应用场景且完全独立，因此是“多平台多应用”的模式。而Hadoop在底层共用一份HDFS存储，上层有很多个组件分别服务多种应用场景，如：
服务层
服务层是包装底层引擎的编程API细节，对业务人员提供更高抽象的访问模型，如Pig、Hive等。
而其中最炙手可热的就是OLAP的SQL市场了。现在，Spark有70%的访问量来自于SparkSQL！
SQL on Hadoop到底哪家强？Hive、Facebook的Pheonix、Presto、SparkSQL、Cloudera推的Impala、MapR推的Drill、IBM的BigSQL、还是Pivital开源的HAWQ？
centos 7无法用公用源安装ceph, 包依赖不满足
centos 6可以安装，但内核不支持rbd,需要更新内核
rpm --importhttp://elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvhhttp://elrepo.org/elrepo-release-6-5.el6.elrepo.noarch.rpm
yum --enablerepo=elrepo-kernel install kernel-lt-y ）
vi /etc/selinux/config
reboot
egrep '(vmx|svm)' --color=always /proc/cpuinfo
空代表不支持
rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY*
yum install virt-manager libvirt qemu-kvm openssh-askpass kvm python-virtinst
service libvirtd start
chkconfig libvirtd on
emulator 一般是qemu-kvm,也可能是其他。
/usr/libexec/qemu-kvm -M ? 查看支持的host系统类型 (我碰到的情况，启动虚拟机时提示host类型rhel6.5不支持，virsh edit ...将host中的rhel6.5改为pc通过)
/usr/libexec/qemu-kvm -drive format=? 查看支持的设备类型 (必须支持rbd,如果没有显示，需要安装支持的版本。源码安装git clone git://git.qemu.org/qemu.git;./configure --enable-rbd。 可能未必产生qemu-kvm，也许是qemu-system-x86_64之类的，那就需要在配置文件里将emulator换成编译好的可执行文件)
yum install bridge-utils
vi /etc/sysconfig/network-scripts/ifcfg-br0
DEVICE="br0"
NM_CONTROLLED="no"
ONBOOT=yes
TYPE=Bridge
BOOTPROTO=none
IPADDR=192.168.0.100
PREFIX=24
GATEWAY=192.168.0.1
DNS1=8.8.8.8
DNS2=8.8.4.4
DEFROUTE=yes
IPV4_FAILURE_FATAL=yes
IPV6INIT=no
NAME="System br0"
vi /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE="eth0"
NM_CONTROLLED="no"
ONBOOT=yes
TYPE="Ethernet"
UUID="73cb0b12-1f42-49b0-ad69-731e888276ff"
HWADDR=00:1E:90:F3:F0:02
DEFROUTE=yes
IPV4_FAILURE_FATAL=yes
IPV6INIT=no
NAME="System eth0"
BRIDGE=br0
/etc/init.d/network restart
virt-install --connect qemu:///system -n vm10 -r 512 --vcpus=2 --disk path=/var/lib/libvirt/images/vm10.img,size=12 -c /dev/cdrom --vnc --noautoconsole --os-type linux --os-variant debiansqueeze --accelerate --network=bridge:br0 --hvm
如果需要安装gui
yum -y groupinstall "Desktop" "Desktop Platform" "X Window System" "Fonts"
一台安装管理机:admin
一台monitor:node1
两台数据机osd: node2, node3
一台使用ceph rbd的客户端: ceph-client
所有机器上都创建ceph用户，给予sudo权限，所以后续命令以ceph用户执行。
所有机器关闭 selinux
所有机器关闭Defaults requiretty（sudo visudo）
所有机器检查iptables等防火墙设置，节点间通讯使用22,6789,6800等端口，防止被拒绝
添加repo
sudo vim /etc/yum.repos.d/ceph.repo
[ceph-noarch]
name=Ceph noarch packages
baseurl=http://ceph.com/rpm-{ceph-release}/{distro}/noarch
enabled=1
gpgcheck=1
type=rpm-md
gpgkey=https://ceph.com/git/?p=ceph.git;a=blob_plain;f=keys/release.asc
我将baseurl替换为baseurl=http://ceph.com/rpm-firefly/el6/noarch
执行sudo yum update && sudo yum install ceph-deploy
使得admin用ssh key登陆其他机器
ssh-keygen
ssh-copy-id ceph@node1
ssh-copy-id ceph@node2
ssh-copy-id ceph@node3
admin机器上
mkdir my-cluster
cd my-cluster
初始化配置：
ceph-deploy new node1
此时会在当前目录下创建配置文件ceph.conf，编辑ceph.conf,
添加osd pool default size = 2， 这是因为我们只有2个osd
添加rbd default format = 2, 将默认的rbd image格式设置为2，支持image的clone功能
添加journal dio = false，
在所有节点上安装ceph
ceph-deploy install admin node1 node2 node3
初始化监控节点
ceph-deploy mon create-initial node1
初始化osd节点
ssh node2
sudo mkdir /var/local/osd0
exit
ssh node3
sudo mkdir /var/local/osd1
exit
ceph-deploy osd prepare node2:/var/local/osd0 node3:/var/local/osd1
ceph-deploy osd activate node2:/var/local/osd0 node3:/var/local/osd1
（此处两个命令应该在数秒内结束，若长时间不响应直至300秒超时，考虑是否有防火墙因素。）
将配置拷贝到各个节点
ceph-deploy admin admin-node node1 node2 node3
sudo chmod +r /etc/ceph/ceph.client.admin.keyring
ceph health
ceph status
希望得到active_clean状态
ceph osd pool create libvirt-pool 128 128
假设我们使用的账号是libvirt(如果使用admin账号默认拥有所有权限，无需设置)
ceph auth get-or-create client.libvirt mon 'allow r' osd 'allow class-read object_prefix rbd_children, allow rwx pool=libvirt-pool'
qemu-img create -f rbd rbd:libvirt-pool/new-libvirt-image 10G
这一步我遇到了Unknown file format 'rbd', 这是因为低版本的qemu-img不支持rbd.
但是我的qemu-img版本号已经够了，猜测是我的包在编译时没有加rbd的选项。无奈强制安装了版本号更低的 http://ceph.com/packages/qemu-kvm/centos/x86_64/qemu-img-0.12.1.2-2.355.el6.2.cuttlefish.x86_64.rpm 才支持)
rbd -p libvirt-pool ls
1. 用virsh命令或virt-manager创建一个虚拟机
需要一个iso或img 在/var/lib/libvirt/images/下
我将它命名为test。 cd rom中选择一个iso,比如debian.iso.不选硬盘。
2. virsh edit test
将该vm的配置修改为使用rbd存储
找到
<devices>
在其后添加如下：
<disk type='network' device='disk'>
<source protocol='rbd' name='libvirt-pool/new-libvirt-image'>
<host name='{monitor-host}' port='6789'/>
</source>
<target dev='vda' bus='virtio'/>
</disk>
3. 创建访问ceph的账号
cat > secret.xml <<EOF
<secret ephemeral='no' private='no'>
<usage type='ceph'>
<name>client.libvirt secret</name>
</usage>
</secret>
EOF
sudo virsh secret-define --file secret.xml
<uuid of secret is output here>
保存用户libvirt的key
ceph auth get-key client.libvirt | sudo tee client.libvirt.key
保存产生的uuid
sudo virsh secret-set-value --secret {uuid of secret} --base64 $(cat client.libvirt.key) && rm client.libvirt.key secret.xml
virsh edit test
add auth
...
</source>
<auth username='libvirt'>
<secret type='ceph' uuid='9ec59067-fdbc-a6c0-03ff-df165c0587b8'/>
</auth>
4. 开启虚拟机安装os
同时 virsh edit test
将配置的boot方式从cdrom改为hd
5.安装结束重启虚拟机,会boot from vda，也就是rbd
6. 下一步可以使用rbd snap, rdb clone, virsh, guestfs制作和使用虚拟机模板
virt-install(1) - Linux man page
Name
virt-install - provision new virtual machines
Synopsis
virt-install [ OPTION ]...
Description
virt-install is a command line tool for creating new KVM , Xen, or Linux container guests using the "libvirt" hypervisor management library. See the EXAMPLES section at the end of this document to quickly get started.
virt-install tool supports both text based & graphical installations, using VNC or SDL graphics, or a text serial console. The guest can be configured to use one or more virtual disks, network interfaces, audio devices, physical USB or PCI devices, among others.
The installation media can be held locally or remotely on NFS , HTTP , FTP servers. In the latter case "virt-install" will fetch the minimal files necessary to kick off the installation process, allowing the guest to fetch the rest of the OS distribution as needed. PXE booting, and importing an existing disk image (thus skipping the install phase) are also supported.
Given suitable command line arguments, "virt-install" is capable of running completely unattended, with the guest 'kickstarting' itself too. This allows for easy automation of guest installs. An interactive mode is also available with the --prompt option, but this will only ask for the minimum required options.
Options
Most options are not required. Minimum requirements are --name, --ram, guest storage (--disk, --filesystem or --nodisks), and an install option.
-h, --help
Show the help message and exit
--connect=CONNECT
Connect to a non-default hypervisor. The default connection is chosen based on the following rules:
xenIf running on a host with the Xen kernel (checks against /proc/xen)
qemu:///system
If running on a bare metal kernel as root (needed for KVM installs)
qemu:///session
If running on a bare metal kernel as non-rootIt is only necessary to provide the "--connect" argument if this default prioritization is incorrect, eg if wanting to use QEMU while on a Xen kernel.
General Options
General configuration parameters that apply to all types of guest installs.
-n NAME , --name=NAME
Name of the new guest virtual machine instance. This must be unique amongst all guests known to the hypervisor on the connection, including those not currently active. To re-define an existing guest, use the virsh(1) tool to shut it down ('virsh shutdown') & delete ('virsh undefine') it prior to running "virt-install".
-r MEMORY , --ram=MEMORY
Memory to allocate for guest instance in megabytes. If the hypervisor does not have enough free memory, it is usual for it to automatically take memory away from the host operating system to satisfy this allocation.
--arch=ARCH
Request a non-native CPU architecture for the guest virtual machine. If omitted, the host CPU architecture will be used in the guest.
--machine=MACHINE
The machine type to emulate. This will typically not need to be specified for Xen or KVM , but is useful for choosing machine types of more exotic architectures.
-u UUID , --uuid=UUID
UUID for the guest; if none is given a random UUID will be generated. If you specify UUID , you should use a 32-digit hexadecimal number. UUID are intended to be unique across the entire data center, and indeed world. Bear this in mind if manually specifying a UUID
--vcpus=VCPUS[,maxvcpus=MAX][,sockets=#][,cores=#][,threads=#]
Number of virtual cpus to configure for the guest. If 'maxvcpus' is specified, the guest will be able to hotplug up to MAX vcpus while the guest is running, but will startup with VCPUS .CPU topology can additionally be specified with sockets, cores, and threads. If values are omitted, the rest will be autofilled prefering sockets over cores over threads.
--cpuset=CPUSET
Set which physical cpus the guest can use. "CPUSET" is a comma separated list of numbers, which can also be specified in ranges or cpus to exclude. Example:
0,2,3,5 : Use processors 0,2,3 and 5
1-5,^3,8 : Use processors 1,2,4,5 and 8
If the value 'auto' is passed, virt-install attempts to automatically determine an optimal cpu pinning using NUMA data, if available.
--numatune=NODESET,[mode=MODE]
Tune NUMA policy for the domain process. Example invocations
--numatune 1,2,3,4-7
--numatune \"1-3,5\",mode=preferred
Specifies the numa nodes to allocate memory from. This has the same syntax as "--cpuset" option. mode can be one of 'interleave', 'preferred', or 'strict' (the default). See 'man 8 numactl' for information about each mode.The nodeset string must use escaped-quotes if specifying any other option.
--cpu MODEL[,+feature][,-feature][,match=MATCH][,vendor=VENDOR]
Configure the CPU model and CPU features exposed to the guest. The only required value is MODEL , which is a valid CPU model as listed in libvirt's cpu_map.xml file.Specific CPU features can be specified in a number of ways: using one of libvirt's feature policy values force, require, optional, disable, or forbid, or with the shorthand '+feature' and '-feature', which equal 'force=feature' and 'disable=feature' respectivelySome examples:
--cpu core2duo,+x2apic,disable=vmx
Expose the core2duo CPU model, force enable x2apic, but do not expose vmx
--cpu host
Expose the host CPUs configuration to the guest. This enables the guest to take advantage of many of the host CPUs features (better performance), but may cause issues if migrating the guest to a host without an identical CPU .
--description
Human readable text description of the virtual machine. This will be stored in the guests XML configuration for access by other applications.
--security type=TYPE[,label=LABEL][,relabel=yes|no]
Configure domain security driver settings. Type can be either 'static' or 'dynamic'. 'static' configuration requires a security LABEL . Specifying LABEL without TYPE implies static configuration. To have libvirt automatically apply your static label, you must specify relabel=yes.
Installation Method options
-c CDROM , --cdrom=CDROM
File or device use as a virtual CD-ROM device for fully virtualized guests. It can be path to an ISO image, or to a CDROM device. It can also be a URL from which to fetch/access a minimal boot ISO image. The URLs take the same format as described for the "--location" argument. If a cdrom has been specified via the "--disk" option, and neither "--cdrom" nor any other install option is specified, the "--disk" cdrom is used as the install media.
-l LOCATION , --location=LOCATION
Distribution tree installtion source. virt-install can recognize certain distribution trees and fetches a bootable kernel/initrd pair to launch the install.With libvirt 0.9.4 or later, network URL installs work for remote connections. virt-install will download kernel/initrd to the local machine, and then upload the media to the remote host. This option requires the URL to be accessible by both the local and remote host.The "LOCATION" can take one of the following forms:
DIRECTORY
Path to a local directory containing an installable distribution image
nfs:host:/path or nfs://host/path
An NFS server location containing an installable distribution image
http://host/path
An HTTP server location containing an installable distribution image
ftp://host/path
An FTP server location containing an installable distribution image
Some distro specific url samples:
Fedora/Red Hat Based
http://download.fedoraproject.org/pub/fedora/linux/releases/10/Fedora/i386/os/
Debian/Ubuntu
http://ftp.us.debian.org/debian/dists/etch/main/installer-amd64/
Suse
http://download.opensuse.org/distribution/11.0/repo/oss/
Mandriva
ftp://ftp.uwsg.indiana.edu/linux/mandrake/official/2009.0/i586/
--pxe
Use the PXE boot protocol to load the initial ramdisk and kernel for starting the guest installation process.
--import
Skip the OS installation process, and build a guest around an existing disk image. The device used for booting is the first device specified via "--disk" or "--filesystem".
--init=INITPATH
Path to a binary that the container guest will init. If a root "--filesystem" is has been specified, virt-install will default to /sbin/init, otherwise will default to /bin/sh.
--livecd
Specify that the installation media is a live CD and thus the guest needs to be configured to boot off the CDROM device permanently. It may be desirable to also use the "--nodisks" flag in combination.
-x EXTRA , --extra-args=EXTRA
Additional kernel command line arguments to pass to the installer when performing a guest install from "--location". One common usage is specifying an anaconda kickstart file for automated installs, such as --extra-args "ks=http://myserver/my.ks"
--initrd-inject=PATH
Add PATH to the root of the initrd fetched with "--location". This can be used to run an automated install without requiring a network hosted kickstart file:--initrd-inject=/path/to/my.ks --extra-args "ks=file:/my.ks"
--os-type=OS_TYPE
Optimize the guest configuration for a type of operating system (ex. 'linux', 'windows'). This will attempt to pick the most suitable ACPI & APIC settings, optimally supported mouse drivers, virtio, and generally accommodate other operating system quirks.By default, virt-install will attempt to auto detect this value from the install media (currently only supported for URL installs). Autodetection can be disabled with the special value 'none'See "--os-variant" for valid options.
--os-variant=OS_VARIANT
Further optimize the guest configuration for a specific operating system variant (ex. 'fedora8', 'winxp'). This parameter is optional, and does not require an "--os-type" to be specified.By default, virt-install will attempt to auto detect this value from the install media (currently only supported for URL installs). Autodetection can be disabled with the special value 'none'.If the special value 'list' is passed, virt-install will print the full list of variant values and exit. The printed format is not a stable interface, DO NOT PARSE IT .If the special value 'none' is passed, no os variant is recorded and OS autodetection is disabled.Values for some recent OS options are:
win7 : Microsoft Windows 7
vista : Microsoft Windows Vista
winxp64 : Microsoft Windows XP (x86_64)
winxp : Microsoft Windows XP
win2k8 : Microsoft Windows Server 2008
win2k3 : Microsoft Windows Server 2003
freebsd8 : FreeBSD 8.x
generic : Generic
debiansqueeze : Debian Squeeze
debianlenny : Debian Lenny
fedora16 : Fedora 16
fedora15 : Fedora 15
fedora14 : Fedora 14
mes5.1 : Mandriva Enterprise Server 5.1 and later
mandriva2010 : Mandriva Linux 2010 and later
rhel6 : Red Hat Enterprise Linux 6
rhel5.4 : Red Hat Enterprise Linux 5.4 or later
rhel4 : Red Hat Enterprise Linux 4
sles11 : Suse Linux Enterprise Server 11
sles10 : Suse Linux Enterprise Server
ubuntuoneiric : Ubuntu 11.10 (Oneiric Ocelot)
ubuntunatty : Ubuntu 11.04 (Natty Narwhal)
ubuntumaverick : Ubuntu 10.10 (Maverick Meerkat)
ubuntulucid : Ubuntu 10.04 (Lucid Lynx)
ubuntuhardy : Ubuntu 8.04 LTS (Hardy Heron)
Use '--os-variant list' to see the full OS list
--boot=BOOTOPTS
Optionally specify the post-install VM boot configuration. This option allows specifying a boot device order, permanently booting off kernel/initrd with option kernel arguments, and enabling a BIOS boot menu (requires libvirt 0.8.3 or later)--boot can be specified in addition to other install options (such as --location, --cdrom, etc.) or can be specified on it's own. In the latter case, behavior is similar to the --import install option: there is no 'install' phase, the guest is just created and launched as specified.Some examples:
--boot cdrom,fd,hd,network,menu=on
Set the boot device priority as first cdrom, first floppy, first harddisk, network PXE boot. Additionally enable BIOS boot menu prompt.
--boot kernel=KERNEL,initrd=INITRD,kernel_args="console=/dev/ttyS0"
Have guest permanently boot off a local kernel/initrd pair, with the specified kernel options.
Storage Configuration
--disk=DISKOPTS
Specifies media to use as storage for the guest, with various options. The general format of a disk string is
--disk opt1=val1,opt2=val2,...
To specify media, the command can either be:
--disk /some/storage/path,opt1=val1
or explicitly specify one of the following arguments:
path
A path to some storage media to use, existing or not. Existing media can be a file or block device. If installing on a remote host, the existing media must be shared as a libvirt storage volume.Specifying a non-existent path implies attempting to create the new storage, and will require specifyng a 'size' value. If the base directory of the path is a libvirt storage pool on the host, the new storage will be created as a libvirt storage volume. For remote hosts, the base directory is required to be a storage pool if using this method.
pool
An existing libvirt storage pool name to create new storage on. Requires specifying a 'size' value.
volAn existing libvirt storage volume to use. This is specified as 'poolname/volname'.
Other available options:
device
Disk device type. Value can be 'cdrom', 'disk', or 'floppy'. Default is 'disk'. If a 'cdrom' is specified, and no install method is chosen, the cdrom is used as the install media.
busDisk bus type. Value can be 'ide', 'scsi', 'usb', 'virtio' or 'xen'. The default is hypervisor dependent since not all hypervisors support all bus types.
perms
Disk permissions. Value can be 'rw' (Read/Write), 'ro' (Readonly), or 'sh' (Shared Read/Write). Default is 'rw'
size
size (in GB ) to use if creating new storage
sparse
whether to skip fully allocating newly created storage. Value is 'true' or 'false'. Default is 'true' (do not fully allocate).The initial time taken to fully-allocate the guest virtual disk (sparse=false) will be usually by balanced by faster install times inside the guest. Thus use of this option is recommended to ensure consistently high performance and to avoid I/O errors in the guest should the host filesystem fill up.
cache
The cache mode to be used. The host pagecache provides cache memory. The cache value can be 'none', 'writethrough', or 'writeback'. 'writethrough' provides read caching. 'writeback' provides read and write caching.
format
Image format to be used if creating managed storage. For file volumes, this can be 'raw', 'qcow2', 'vmdk', etc. See format types in <http://libvirt.org/storage.html> for possible values. This is often mapped to the driver_type value as well.With libvirt 0.8.3 and later, this option should be specified if reusing and existing disk image, since libvirt does not autodetect storage format as it is a potential security issue. For example, if reusing an existing qcow2 image, you will want to specify format=qcow2, otherwise the hypervisor may not be able to read your disk image.
driver_name
Driver name the hypervisor should use when accessing the specified storage. Typically does not need to be set by the user.
driver_type
Driver format/type the hypervisor should use when accessing the specified storage. Typically does not need to be set by the user.
ioDisk IO backend. Can be either "threads" or "native".
error_policy
How guest should react if a write error is encountered. Can be one of "stop", "none", or "enospace"
serial
Serial number of the emulated disk device. This is used in linux guests to set /dev/disk/by-id symlinks. An example serial number might be: WD-WMAP9A966149
See the examples section for some uses. This option deprecates "--file", "--file-size", and "--nonsparse".
--filesystem
Specifies a directory on the host to export to the guest. The most simple invocation is:
--filesystem /source/on/host,/target/point/in/guest
Which will work for recent QEMU and linux guest OS or LXC containers. For QEMU , the target point is just a mounting hint in sysfs, so will not be automatically mounted.The following explicit options can be specified:
type
The type or the source directory. Valid values are 'mount' (the default) or 'template' for OpenVZ templates.
mode
The access mode for the source directory from the guest OS . Only used with QEMU and type=mount. Valid modes are 'passthrough' (the default), 'mapped', or 'squash'. See libvirt domain XML documentation for more info.
source
The directory on the host to share.
target
The mount location to use in the guest.
--nodisks
Request a virtual machine without any local disk storage, typically used for running 'Live CD ' images or installing to network storage (iSCSI or NFS root).
-f DISKFILE , --file=DISKFILE
This option is deprecated in favor of "--disk path=DISKFILE".
-s DISKSIZE , --file-size=DISKSIZE
This option is deprecated in favor of "--disk ...,size=DISKSIZE,..."
--nonsparse
This option is deprecated in favor of "--disk ...,sparse=false,..."
Networking Configuration
-w NETWORK , --network=NETWORK,opt1=val1,opt2=val2
Connect the guest to the host network. The value for "NETWORK" can take one of 3 formats:
bridge=BRIDGE
Connect to a bridge device in the host called "BRIDGE". Use this option if the host has static networking config & the guest requires full outbound and inbound connectivity to/from the LAN . Also use this if live migration will be used with this guest.
network=NAME
Connect to a virtual network in the host called "NAME". Virtual networks can be listed, created, deleted using the "virsh" command line tool. In an unmodified install of "libvirt" there is usually a virtual network with a name of "default". Use a virtual network if the host has dynamic networking (eg NetworkManager), or using wireless. The guest will be NATed to the LAN by whichever connection is active.
user
Connect to the LAN using SLIRP . Only use this if running a QEMU guest as an unprivileged user. This provides a very limited form of NAT .
If this option is omitted a single NIC will be created in the guest. If there is a bridge device in the host with a physical interface enslaved, that will be used for connectivity. Failing that, the virtual network called "default" will be used. This option can be specified multiple times to setup more than one NIC .Other available options are:
model
Network device model as seen by the guest. Value can be any nic model supported by the hypervisor, e.g.: 'e1000', 'rtl8139', 'virtio', ...
mac Fixed MAC address for the guest; If this parameter is omitted, or the value "RANDOM" is specified a suitable address will be randomly generated. For Xen virtual machines it is required that the first 3 pairs in the MAC address be the sequence '00:16:3e', while for QEMU or KVM virtual machines it must be '52:54:00'.
--nonetworks
Request a virtual machine without any network interfaces.
-b BRIDGE , --bridge=BRIDGE
This parameter is deprecated in favour of "--network bridge=bridge_name".
-m MAC , --mac=MAC
This parameter is deprecated in favour of "--network NETWORK,mac=12:34..."
Graphics Configuration
If no graphics option is specified, "virt-install" will default to '--graphics vnc' if the DISPLAY environment variable is set, otherwise '--graphics none' is used.
--graphics TYPE ,opt1=arg1,opt2=arg2,...
Specifies the graphical display configuration. This does not configure any virtual hardware, just how the guest's graphical display can be accessed. Typically the user does not need to specify this option, virt-install will try and choose a useful default, and launch a suitable connection.General format of a graphical string is
--graphics TYPE,opt1=arg1,opt2=arg2,...
For example:
--graphics vnc,password=foobar
The supported options are:
type
The display type. This is one of:vnc
Setup a virtual console in the guest and export it as a VNC server in the host. Unless the "port" parameter is also provided, the VNC server will run on the first free port number at 5900 or above. The actual VNC display allocated can be obtained using the "vncdisplay" command to "virsh" (or virt-viewer(1) can be used which handles this detail for the use).
sdl
Setup a virtual console in the guest and display an SDL window in the host to render the output. If the SDL window is closed the guest may be unconditionally terminated.
spice
Export the guest's console using the Spice protocol. Spice allows advanced features like audio and USB device streaming, as well as improved graphical performance.
Using spice graphic type will work as if those arguments were given:
--video qxl --channel spicevmc
noneNo graphical console will be allocated for the guest. Fully virtualized guests (Xen FV or QEmu/KVM) will need to have a text console configured on the first serial port in the guest (this can be done via the --extra-args option). Xen PV will set this up automatically. The command 'virsh console NAME ' can be used to connect to the serial device.
port
Request a permanent, statically assigned port number for the guest console. This is used by 'vnc' and 'spice'
tlsport
Specify the spice tlsport.
listen
Address to listen on for VNC/Spice connections. Default is typically 127.0.0.1 (localhost only), but some hypervisors allow changing this globally (for example, the qemu driver default can be changed in /etc/libvirt/qemu.conf). Use 0.0.0.0 to allow access from other machines. This is use by 'vnc' and 'spice'
keymap
Request that the virtual VNC console be configured to run with a specific keyboard layout. If the special value 'local' is specified, virt-install will attempt to configure to use the same keymap as the local system. A value of 'none' specifically defers to the hypervisor. Default behavior is hypervisor specific, but typically is the same as 'local'. This is used by 'vnc'
password
Request a VNC password, required at connection time. Beware, this info may end up in virt-install log files, so don't use an important password. This is used by 'vnc' and 'spice'
passwordvalidto
Set an expiration date for password. After the date/time has passed, all new graphical connections are denyed until a new password is set. This is used by 'vnc' and 'spice'The format for this value is YYYY-MM-DDTHH:MM:SS , for example 2011-04-01T14:30:15
--vnc
This option is deprecated in favor of "--graphics vnc,..."
--vncport=VNCPORT
This option is deprecated in favor of "--graphics vnc,port=PORT,..."
--vnclisten=VNCLISTEN
This option is deprecated in favor of "--graphics vnc,listen=LISTEN,..."
-k KEYMAP , --keymap=KEYMAP
This option is deprecated in favor of "--graphics vnc,keymap=KEYMAP,..."
--sdl
This option is deprecated in favor of "--graphics sdl,..."
--nographics
This option is deprecated in favor of "--graphics none"
--noautoconsole
Don't automatically try to connect to the guest console. The default behaviour is to launch a VNC client to display the graphical console, or to run the "virsh" "console" command to display the text console. Use of this parameter will disable this behaviour.
Virtualization Type options
Options to override the default virtualization type choices.
-v, --hvm
Request the use of full virtualization, if both para & full virtualization are available on the host. This parameter may not be available if connecting to a Xen hypervisor on a machine without hardware virtualization support. This parameter is implied if connecting to a QEMU based hypervisor.
-p, --paravirt
This guest should be a paravirtualized guest. If the host supports both para & full virtualization, and neither this parameter nor the "--hvm" are specified, this will be assumed.
--container
This guest should be a container type guest. This option is only required if the hypervisor supports other guest types as well (so for example this option is the default behavior for LXC and OpenVZ, but is provided for completeness).
--virt-type
The hypervisor to install on. Example choices are kvm, qemu, xen, or kqemu. Availabile options are listed via 'virsh capabilities' in the <domain> tags.
--accelerate
Prefer KVM or KQEMU (in that order) if installing a QEMU guest. This behavior is now the default, and this option is deprecated. To install a plain QEMU guest, use '--virt-type qemu'
--noapic
Force disable APIC for the guest.
--noacpi
Force disable ACPI for the guest.
Device Options
--host-device=HOSTDEV
Attach a physical host device to the guest. Some example values for HOSTDEV:
--host-device pci_0000_00_1b_0
A node device name via libvirt, as shown by 'virsh nodedev-list'
--host-device 001.003
USB by bus, device (via lsusb).
--host-device 0x1234:0x5678
USB by vendor, product (via lsusb).
--host-device 1f.01.02
PCI device (via lspci).
--soundhw MODEL
Attach a virtual audio device to the guest. MODEL specifies the emulated sound card model. Possible values are ich6, ac97, es1370, sb16, pcspk, or default. 'default' will be AC97 if the hypervisor supports it, otherwise it will be ES1370 .This deprecates the old boolean --sound model (which still works the same as a single '--soundhw default')
--watchdog MODEL[,action=ACTION]
Attach a virtual hardware watchdog device to the guest. This requires a daemon and device driver in the guest. The watchdog fires a signal when the virtual machine appears to hung. ACTION specifies what libvirt will do when the watchdog fires. Values are
reset
Forcefully reset the guest (the default)
poweroff
Forcefully power off the guest
pause
Pause the guest
none
Do nothing
shutdown
Gracefully shutdown the guest (not recommended, since a hung guest probably won't respond to a graceful shutdown)
MODEL is the emulated device model: either i6300esb (the default) or ib700. Some examples:Use the recommended settings:--watchdog defaultUse the i6300esb with the 'poweroff' action--watchdog i6300esb,action=poweroff
--parallel=CHAROPTS
--serial=CHAROPTS
Specifies a serial device to attach to the guest, with various options. The general format of a serial string is
--serial type,opt1=val1,opt2=val2,...
--serial and --parallel devices share all the same options, unless otherwise noted. Some of the types of character device redirection are:
--serial pty
Pseudo TTY . The allocated pty will be listed in the running guests XML description.
--serial dev,path=HOSTPATH
Host device. For serial devices, this could be /dev/ttyS0. For parallel devices, this could be /dev/parport0.
--serial file,path=FILENAME
Write output to FILENAME .
--serial pipe,path=PIPEPATH
Named pipe (see pipe(7))
--serial tcp,host=HOST:PORT,mode=MODE,protocol=PROTOCOL
TCP net console. MODE is either 'bind' (wait for connections on HOST:PORT ) or 'connect' (send output to HOST:PORT ), default is 'connect'. HOST defaults to '127.0.0.1', but PORT is required. PROTOCOL can be either 'raw' or 'telnet' (default 'raw'). If 'telnet', the port acts like a telnet server or client. Some examples:Connect to localhost, port 1234:
--serial tcp,host=:1234
Wait for connections on any address, port 4567:
--serial tcp,host=0.0.0.0:4567,mode=bind
Wait for telnet connection on localhost, port 2222. The user could then connect interactively to this console via 'telnet localhost 2222':
--serial tcp,host=:2222,mode=bind,protocol=telnet
--serial udp,host=CONNECT_HOST:PORT,bind_host=BIND_HOST:BIND_PORT
UDP net console. HOST:PORT is the destination to send output to (default HOST is '127.0.0.1', PORT is required). BIND_HOST:BIND_PORT is the optional local address to bind to (default BIND_HOST is 127.0.0.1, but is only set if BIND_PORT is specified). Some examples:Send output to default syslog port (may need to edit /etc/rsyslog.conf accordingly):
--serial udp,host=:514
Send output to remote host 192.168.10.20, port 4444 (this output can be read on the remote host using 'nc -u -l 4444'):
--serial udp,host=192.168.10.20:4444
--serial unix,path=UNIXPATH,mode=MODE
Unix socket, see unix(7). MODE has similar behavior and defaults as --serial tcp,mode=MODE
--channel
Specifies a communication channel device to connect the guest and host machine. This option uses the same options as --serial and --parallel for specifying the host/source end of the channel. Extra 'target' options are used to specify how the guest machine sees the channel.Some of the types of character device redirection are:
--channel SOURCE ,target_type=guestfwd,target_address=HOST:PORT
Communication channel using QEMU usermode networking stack. The guest can connect to the channel using the specified HOST:PORT combination.
--channel SOURCE ,target_type=virtio[,name=NAME]
Communication channel using virtio serial (requires 2.6.34 or later host and guest). Each instance of a virtio --channel line is exposed in the guest as /dev/vport0p1, /dev/vport0p2, etc. NAME is optional metadata, and can be any string, such as org.linux-kvm.virtioport1. If specified, this will be exposed in the guest at /sys/class/virtio-ports/vport0p1/NAME
--channel spicevmc,target_type=virtio[,name=NAME]
Communication channel for QEMU spice agent, using virtio serial (requires 2.6.34 or later host and guest). NAME is optional metadata, and can be any string, such as the default com.redhat.spice.0 that specifies how the guest will see the channel.
--console
Connect a text console between the guest and host. Certain guest and hypervisor combinations can automatically set up a getty in the guest, so an out of the box text login can be provided (target_type=xen for xen paravirt guests, and possibly target_type=virtio in the future).Example:
--console pty,target_type=virtio
Connect a virtio console to the guest, redirected to a PTY on the host. For supported guests, this exposes /dev/hvc0 in the guest. See http://fedoraproject.org/wiki/Features/VirtioSerial for more info. virtio console requires libvirt 0.8.3 or later.
--video=VIDEO
Specify what video device model will be attached to the guest. Valid values for VIDEO are hypervisor specific, but some options for recent kvm are cirrus, vga, qxl, or vmvga (vmware).
--smartcard=MODE[,OPTS]
Configure a virtual smartcard device.Mode is one of host, host-certificates, or passthrough. Additional options are:
type
Character device type to connect to on the host. This is only applicable for passthrough mode.
An example invocation:
--smartcard passthrough,type=spicevmc
Use the smartcard channel of a SPICE graphics device to pass smartcard info to the guest
See "http://libvirt.org/formatdomain.html#elementsSmartcard" for complete details.
Miscellaneous Options
--autostart
Set the autostart flag for a domain. This causes the domain to be started on host boot up.
--print-xml
If the requested guest has no install phase (--import, --boot), print the generated XML instead of defining the guest. By default this WILL do storage creation (can be disabled with --dry-run).If the guest has an install phase, you will need to use --print-step to specify exactly what XML output you want. This option implies --quiet.
--print-step
Acts similarly to --print-xml, except requires specifying which install step to print XML for. Possible values are 1, 2, 3, or all. Stage 1 is typically booting from the install media, and stage 2 is typically the final guest config booting off hardisk. Stage 3 is only relevant for windows installs, which by default have a second install stage. This option implies --quiet.
--noreboot
Prevent the domain from automatically rebooting after the install has completed.
--wait=WAIT
Amount of time to wait (in minutes) for a VM to complete its install. Without this option, virt-install will wait for the console to close (not neccessarily indicating the guest has shutdown), or in the case of --noautoconsole, simply kick off the install and exit. Any negative value will make virt-install wait indefinitely, a value of 0 triggers the same results as noautoconsole. If the time limit is exceeded, virt-install simply exits, leaving the virtual machine in its current state.
--force
Prevent interactive prompts. If the intended prompt was a yes/no prompt, always say yes. For any other prompts, the application will exit.
--dry-run
Proceed through the guest creation process, but do NOT create storage devices, change host device configuration, or actually teach libvirt about the guest. virt-install may still fetch install media, since this is required to properly detect the OS to install.
--prompt
Specifically enable prompting for required information. Default prompting is off (as of virtinst 0.400.0)
--check-cpu
Check that the number virtual cpus requested does not exceed physical CPUs and warn if they do.
-q, --quiet
Only print fatal error messages.
-d, --debug
Print debugging information to the terminal when running the install process. The debugging information is also stored in "$HOME/.virtinst/virt-install.log" even if this parameter is omitted.
Examples
Install a Fedora 13 KVM guest with virtio accelerated disk/network, creating a new 8GB storage file, installing from media in the hosts CDROM drive, auto launching a graphical VNC viewer
# virt-install \
--connect qemu:///system \
--virt-type kvm \
--name demo \
--ram 500 \
--disk path=/var/lib/libvirt/images/demo.img,size=8 \
--graphics vnc \
--cdrom /dev/cdrom \
--os-variant fedora13
Install a Fedora 9 plain QEMU guest, using LVM partition, virtual networking, booting from PXE , using VNC server/viewer
# virt-install \
--connect qemu:///system \
--name demo \
--ram 500 \
--disk path=/dev/HostVG/DemoVM \
--network network=default \
--virt-type qemu
--graphics vnc \
--os-variant fedora9
Install a guest with a real partition, with the default QEMU hypervisor for a different architecture using SDL graphics, using a remote kernel and initrd pair:
# virt-install \
--connect qemu:///system \
--name demo \
--ram 500 \
--disk path=/dev/hdc \
--network bridge=eth1 \
--arch ppc64 \
--graphics sdl \
--location http://download.fedora.redhat.com/pub/fedora/linux/core/6/x86_64/os/
Run a Live CD image under Xen fullyvirt, in diskless environment
# virt-install \
--hvm \
--name demo \
--ram 500 \
--nodisks \
--livecd \
--graphics vnc \
--cdrom /root/fedora7live.iso
Run /usr/bin/httpd in a linux container guest ( LXC ). Resource usage is capped at 512 MB of ram and 2 host cpus:
# virt-install \
--connect lxc:/// \
--name httpd_guest \
--ram 512 \
--vcpus 2 \
--init /usr/bin/httpd
Install a paravirtualized Xen guest, 500 MB of RAM , a 5 GB of disk, and Fedora Core 6 from a web server, in text-only mode, with old style --file options:
# virt-install \
--paravirt \
--name demo \
--ram 500 \
--file /var/lib/xen/images/demo.img \
--file-size 6 \
--graphics none \
--location http://download.fedora.redhat.com/pub/fedora/linux/core/6/x86_64/os/
Create a guest from an existing disk image 'mydisk.img' using defaults for the rest of the options.
# virt-install \
--name demo
--ram 512
--disk /home/user/VMs/mydisk.img
--import
Test a custom kernel/initrd using an existing disk image, manually specifying a serial device hooked to a PTY on the host machine.
# virt-install \
--name mykernel
--ram 512
--disk /home/user/VMs/mydisk.img
--boot kernel=/tmp/mykernel,initrd=/tmp/myinitrd,kernel_args="console=ttyS0"
--serial pty
Authors
Written by Daniel P. Berrange, Hugh Brock, Jeremy Katz, Cole Robinson and a team of many other contributors. See the AUTHORS file in the source distribution for the complete list of credits.
links:
https://linux.die.net/man/1/virt-install
https://libvirt.org/formatdomain.html#elementsDevices
https://www.linux-kvm.org/page/Processor_support
CPU LIST:
x86 qemu64 QEMU Virtual CPU version 1.5.3 x86 phenom AMD Phenom(tm) 9550 Quad-Core Processor x86 core2duo Intel(R) Core(TM)2 Duo CPU T7700 @ 2.40GHz x86 kvm64 Common KVM processor x86 qemu32 QEMU Virtual CPU version 1.5.3 x86 kvm32 Common 32-bit KVM processor x86 coreduo Genuine Intel(R) CPU T2600 @ 2.16GHz x86 486 x86 pentium x86 pentium2 x86 pentium3 x86 athlon QEMU Virtual CPU version 1.5.3 x86 n270 Intel(R) Atom(TM) CPU N270 @ 1.60GHz x86 cpu64-rhel6 QEMU Virtual CPU version (cpu64-rhel6) x86 Conroe Intel Celeron_4x0 (Conroe/Merom Class Core 2) x86 Penryn Intel Core 2 Duo P9xxx (Penryn Class Core 2) x86 Nehalem Intel Core i7 9xx (Nehalem Class Core i7) x86 Nehalem-IBRS Intel Core i7 9xx (Nehalem Core i7, IBRS update)▒U x86 Westmere Westmere E56xx/L56xx/X56xx (Nehalem-C) x86 Westmere-IBRS Westmere E56xx/L56xx/X56xx (IBRS update) x86 SandyBridge Intel Xeon E312xx (Sandy Bridge) x86 SandyBridge-IBRS Intel Xeon E312xx (Sandy Bridge, IBRS update) x86 IvyBridge Intel Xeon E3-12xx v2 (Ivy Bridge) x86 IvyBridge-IBRS Intel Xeon E3-12xx v2 (Ivy Bridge, IBRS) x86 Haswell Intel Core Processor (Haswell) x86 Haswell-IBRS Intel Core Processor (Haswell, IBRS) x86 Broadwell Intel Core Processor (Broadwell) x86 Broadwell-IBRS Intel Core Processor (Broadwell, IBRS) x86 Skylake-Client Intel Core Processor (Skylake) x86 Skylake-Client-IBRS Intel Core Processor (Skylake, IBRS) x86 Skylake-Server Intel Xeon Processor (Skylake) x86 Skylake-Server-IBRS Intel Xeon Processor (Skylake, IBRS) x86 Opteron_G1 AMD Opteron 240 (Gen 1 Class Opteron) x86 Opteron_G2 AMD Opteron 22xx (Gen 2 Class Opteron) x86 Opteron_G3 AMD Opteron 23xx (Gen 3 Class Opteron) x86 Opteron_G4 AMD Opteron 62xx class CPU x86 Opteron_G5 AMD Opteron 63xx class CPU x86 EPYC AMD EPYC Processor x86 EPYC-IBPB AMD EPYC Processor (with IBPB) x86 host KVM processor with all supported host features (only available in KVM mode)
########################################
device
'cdrom', 'disk', or 'floppy'.
target bus
"ide", "scsi", "virtio", "xen", "usb", "sata", or "sd"
rbd
<target dev="hda" bus="ide"/>
<target dev="sda" bus="sata"/>
<target dev="sda" bus="scsi"/>
<target dev='vda' bus='virtio'/>
hda
<target dev="sda" bus="ide"/>
lun
<target dev='sda' bus='scsi'/>
iSCSI
<target dev='vda' bus='virtio'/>
1、ceph pool配置
1 创建pool
ceph osd pool create {pool-name} {pg-num} [{pgp-num}]
2 查看pool
ceph osd lspools
3 设置pool的指标pool池中最大存储对象数或最大存储字节数 有其一即可
ceph osd pool set-quota {pool-name} [max_objects{obj-count}] [max_bytes {bytes}]
4 重命名pool
ceph osd pool rename {current-pool-name} {new-pool-name}
5 查看pool的状态
rsdosdf
6 给pool制作快照
ceph osd pool mksnap {pool-name} {snap-name}
7 删除pool的快照
ceph osd pool rmsnap {pool-name} {snap-name}
8 删除一个pool
ceph osd pool delete {pool-name} [{pool-name} --yes-i-really-really-mean-it]
2、ceph pg配置
1 设置pool 中 pgs 的大小
ceph osd poolset {pool-name} pg_num
2 获得 pool 中 pgs 的大小
ceph osd pool get {pool-name} pg_num
3 设置 pool 中 pgs 组的大小
ceph osd poolset {pool-name} pgp_num
4 获得 pool 中 pgs 组的大小
ceph osd poolget {pool-name} pgp_num
5 查看集群中 pgs 的状态
ceph pg dump
6 查看指定pg 的 map
ceph pg map{pg-id}
7 查看指定pg 的状态
ceph pg {pg-id}query
8 清除一个 pg
ceph pg scrub{pg-id}
3、ceph镜像配置
1 查看更新Linux内核版本，
需相应Linux内核支持modproberbd 查看：uname –r
若不支持：
执行下述操作：
sudo rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
sudo rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm
sudo yum --enablerepo=elrepo-kernel install kernel-ml kernel-ml-devel
改为新内核：
sudo grub2-set-default 'CentOS Linux (4.4.0-1.el7.elrepo.x86_64) 7 (Core)'
grub2-editenv list 查看修改
最终更新设置内核：
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
2 创建一个设备的镜像，size以M为单位
rbd create{image-name} --size {megabytes} –pool {pool-name}
如：
rbd createtestImage --size 512 --pool testPool
3 列出一个 pool 里面的块设备，即创建的镜像
rbd list{pool-name}
4 读出一个镜像里面的信息
rbd --image{image-name} -p {pool-name} info
5 重新修改镜像的大小
rbd resize--image {image-name} –p {pool-name} --size 1024
6 将块设备映射到本地
1 sudomodprobe rbd
2 sudo rbd map{image-name} --pool {pool-name}
7 显示映射的模块
rbd showmapped
8 从一个具体的 pool 中删除一个块设备
rbd rm {image-name} -p{pool-name}
9 取消块设备的映射
sudo rbdunmap /dev/rbd/{poolname}/{imagename}
4、ceph快照配置
1 创建快照
1 给镜像创建一个快照
rbd snap create {pool-name}/{image-name}@{snap-name}
2 列出一个镜像的所有快照
rbd snap ls {pool-name}/{image-name}
3 快照回滚
rbd snap rollback {pool-name}/{image-name}@{snap-name}
4 删除快照
rbd snap rm {pool-name}/{image-name}@{snap-name}
5 删除一个镜像的全部快照
rbd snap purge{pool-name}/{image-name}
2 分层快照
1 首先创建一个特殊格式的的镜像，格式要求：format 2
rbd create --image-format 2 {image-name}--size { megabytes } --pool {pool-name}
2 创建快照
rbd snap create {pool-name}/{image-name}@{snap-name}
3 克隆品访问父快照。父快照，所有克隆品都会损坏。为防止数据丢失，必须先保护、然后再克隆快照。
rbd snap protect {pool-name}/{image-name}@{snapshot-name}
$ rbd clone rbd/testImage2@test2Snap rbd/testImage3
4 克隆快照，将一个存储池中的镜像的快照克隆到另一存储池中，成为一个镜像
rbd clone {pool-name}/{parent-image}@{snap-name} {pool-name}/{child-image-name}
5 删除快照
1] 删除方式一：
删除所有快照 取消快照保护 删除快照
2] 删除方式二：
首先将克隆品压缩 解除保护 删除快照
6 取消快照保护
rbd snapunprotect {pool-name}/{image-name}@{snapshot-name}
7 列出一块镜像的子孙
rbd children {pool-name}/{image-name}@{snapshot-name}
8 克隆镜像压缩，进而消除父快照的引用
rbd flatten {pool-name}/{imag
5、ceph qemu配置
1 使用 qemu 创建镜像
qemu-img create-f raw rbd:{pool-name}/{image-name} {size}
例如： qemu-img create -f raw rbd:testPool/testImage0 1G
2 调整 qemu 镜像的大小
qemu-img resizerbd:{pool-name}/{image-name} {size}
3 查看一个 qemu 镜像属性信息
qemu-img inforbd:{pool-name}/{image-name}
4 转换 qemu 其他格式的镜像为块设备镜像
qemu-img convert-p -f 源镜像-O 目标镜像格式文件
rbd:poolname/imagename转换后的文件
5 运行镜像中的虚拟机
qemu -m 内存大小 -driveformat=raw,file=rbd:poolname/imagename
6 qemu 的带缓存控制
1 qemu -m1024 -drive format=rbd,file=rbd:poolname/imagename,cache=writeback
2 qemu –m 1024 \
-driveformat=raw,file=rbd:poolname/imagename:rbd_cache=true,cache=writeback
注：如若设置了rbd_cache=ture那么必须设置cache=writeback或者risk data loss 否则的话，qemu将不会发送请求给librbd如果qemu没有在配置文件中指定清楚，那么基于rbd的上层文件系统可能能被损坏
7 qemu 缓冲操作
回写：
rbd_cache = true
直写：
rbd_cache = ture
rbd_cache_max_dirty = 0
无：
rbd_cache = false
Git命令
Git 是一个很强大的分布式版本控制系统。它不但适用于管理大型开源软件的源代码，管理私人的文档和源代码也有很多优势。
Git常用操作命令：
1) 远程仓库相关命令
检出仓库：$ git clone git://github.com/jquery/jquery.git
查看远程仓库：$ git remote -v
添加远程仓库：$ git remote add [name] [url]
删除远程仓库：$ git remote rm [name]
修改远程仓库：$ git remote set-url --push [name] [newUrl]
拉取远程仓库：$ git pull [remoteName] [localBranchName]
推送远程仓库：$ git push [remoteName] [localBranchName]
*如果想把本地的某个分支test提交到远程仓库，并作为远程仓库的master分支，或者作为另外一个名叫test的分支，如下：
$git push origin test:master // 提交本地test分支作为远程的master分支
$git push origin test:test // 提交本地test分支作为远程的test分支
2）分支(branch)操作相关命令
查看本地分支：$ git branch
查看远程分支：$ git branch -r
创建本地分支：$ git branch [name] ----注意新分支创建后不会自动切换为当前分支
切换分支：$ git checkout [name]
创建新分支并立即切换到新分支：$ git checkout -b [name]
删除分支：$ git branch -d [name] ---- -d选项只能删除已经参与了合并的分支，对于未有合并的分支是无法删除的。如果想强制删除一个分支，可以使用-D选项
合并分支：$ git merge [name] ----将名称为[name]的分支与当前分支合并
创建远程分支(本地分支push到远程)：$ git push origin [name]
git push origin -d {branch or tag}：删除远程分支
*创建空的分支：(执行命令之前记得先提交你当前分支的修改，否则会被强制删干净没得后悔)
$git symbolic-ref HEAD refs/heads/[name]
$rm .git/index
$git clean -fdx
3）版本(tag)操作相关命令
git tag <name>：为当前分支所在的提交记录打上轻量标签。
git tag <name> <commit SHA-1 value>：为某次具体的提交记录打上轻量标签。
git tag -a <name> -m <tag_message>：为当前分支所在的提交记录打上附注标签。
git tag：列出所有的标签名。
git tag -d <tag_name>：删除某个标签，本质上就是移除 .git/refs/tags/ 中对应的文件。
git show <tag_name>：显示标签对应提交记录的具体信息。
git push <remote> <tag_name>：推送某个标签到远程仓库。
git push <remote> --tags：推送所有标签到远程仓库。
git push <remote> --delete <tag_name>：删除远程仓库中的某个标签。
git pull <remote> --tags：合并远程仓库的tag到本地
git push origin --tags：上传本地tag到远程仓库
4) 子模块(submodule)相关操作命令
添加子模块：$ git submodule add [url] [path]
如：$git submodule add git://github.com/soberh/ui-libs.git src/main/webapp/ui-libs
初始化子模块：$ git submodule init ----只在首次检出仓库时运行一次就行
更新子模块：$ git submodule update ----每次更新或切换分支后都需要运行一下
删除子模块：（分4步走哦）
1) $ git rm --cached [path]
2) 编辑“.gitmodules”文件，将子模块的相关配置节点删除掉
3) 编辑“ .git/config”文件，将子模块的相关配置节点删除掉
4) 手动删除子模块残留的目录
5）忽略一些文件、文件夹不提交
在仓库根目录下创建名称为“.gitignore”的文件，写入不需要的文件夹名或文件，每个元素占一行即可，如
target
bin
*.db
=====================
git 切换到远程分支的时候
git branch fenzhi2git checkout fenzhi2 切换到第二个分支git branch --set-upstream-to origin/fenzhi2 关联到第二个分支git log --graph --decorate --oneline --simplify-by-decoration --allgit reset --hard *** 切换到远程分支 fenzhi2 的工作目录。这时候就可以正常使用了由于这个操作太常用了，该捷径本身还有一个捷径。 如果你尝试检出的分支 (a) 不存在且 (b) 刚好只有一个名字与之匹配的远程分支，那么 Git 就会为你创建一个跟踪分支：
$ git checkout serverfix
Branch serverfix set up to track remote branch serverfix from origin.
Switched to a new branch 'serverfix'如果想要将本地分支与远程分支设置为不同的名字，你可以轻松地使用上一个命令增加一个不同名字的本地分支：
$ git checkout -b sf origin/serverfix
Branch sf set up to track remote branch serverfix from origin.
Switched to a new branch 'sf'现在，本地分支 sf 会自动从 origin/serverfix 拉取。
设置已有的本地分支跟踪一个刚刚拉取下来的远程分支，或者想要修改正在跟踪的上游分支， 你可以在任意时间使用 -u 或 --set-upstream-to 选项运行 git branch 来显式地设置。
$ git branch -u origin/serverfix
Branch serverfix set up to track remote branch serverfix from origin.=====================
Git 常用命令
git branch 查看本地所有分支
git status 查看当前状态
git commit 提交
git branch -a 查看所有的分支
git branch -r 查看本地所有分支
git commit -am "init" 提交并且加注释
git remote add origin git@192.168.1.119:ndshow
git push origin master 将文件给推到服务器上
git remote show origin 显示远程库origin里的资源
git push origin master:develop
git push origin master:hb-dev 将本地库与服务器上的库进行关联
git checkout --track origin/dev 切换到远程dev分支
git branch -D master develop 删除本地库develop
git checkout -b dev 建立一个新的本地分支dev
git merge origin/dev 将分支dev与当前分支进行合并
git checkout dev 切换到本地dev分支
git remote show 查看远程库
git add .
git rm 文件名(包括路径) 从git中删除指定文件
git clone git://github.com/schacon/grit.git 从服务器上将代码给拉下来
git config --list 看所有用户
git ls-files 看已经被提交的
git rm [file name] 删除一个文件
git commit -a 提交当前repos的所有的改变
git add [file name] 添加一个文件到git index
git commit -v 当你用－v参数的时候可以看commit的差异
git commit -m "This is the message describing the commit" 添加commit信息
git commit -a -a是代表add，把所有的change加到git index里然后再commit
git commit -a -v 一般提交命令
git log 看你commit的日志
git diff 查看尚未暂存的更新
git rm a.a 移除文件(从暂存区和工作区中删除)
git rm --cached a.a 移除文件(只从暂存区中删除)
git commit -m "remove" 移除文件(从Git中删除)
git rm -f a.a 强行移除修改后文件(从暂存区和工作区中删除)
git diff --cached 或 $ git diff --staged 查看尚未提交的更新
git stash push 将文件给push到一个临时空间中
git stash pop 将文件从临时空间pop下来
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git remote add origin git@github.com:username/Hello-World.git
git push origin master 将本地项目给提交到服务器中
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git pull 本地与服务器端同步
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git push (远程仓库名) (分支名) 将本地分支推送到服务器上去。
git push origin serverfix:awesomebranch
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git fetch 相当于是从远程获取最新版本到本地，不会自动merge
git commit -a -m "log_message" (-a是提交所有改动，-m是加入log信息) 本地修改同步至服务器端 ：
git branch branch_0.1 master 从主分支master创建branch_0.1分支
git branch -m branch_0.1 branch_1.0 将branch_0.1重命名为branch_1.0
git checkout branch_1.0/master 切换到branch_1.0/master分支
du -hs
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mkdir WebApp
cd WebApp
git init
touch README
git add README
git commit -m 'first commit'
git remote add origin git@github.com:daixu/WebApp.git
git push -u origin maste
Git 常用命令速查表
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GIT 配置
您还可以按照以下说明从计算机中上传现有文件。
git config --global user.name "xiaobo" git config --global user.email "xb@mail.org"
git clone https://git.my.org/abc/my.git cd my touch README.md git add README.md git commit -m "add README" git push -u origin master
cd existing_folder git init git remote add origin https://git.my.org/abc/my.git git add . git commit -m "Initial commit" git push -u origin master
cd existing_repo git remote rename origin old-origin git remote add origin https://git.my.org/abc/my.git git push -u origin --all git push -u origin --tags
注：加了参数-u后，以后即可直接用git push 代替git push origin master
git push -u origin master
默认授权
~/.ssh/id_rsa
.
..