linux bios启动虚拟化 linux主机虚拟化

kvm虚拟化

文章目录

• kvm虚拟化

• 1.虚拟化介绍
• 2.kvm介绍
• 3. kvm部署

• 3.1 kvm安装
• 3.2 kvm web管理界面安装
• 3.3 kvm web界面管理

• 3.3.1 kvm连接管理
• 3.3.2 kvm存储管理
• 3.3.3 kvm网络管理
• 3.3.4 实例管理

• 4.故障案例

• 4.1 案例1
• 4.2 案例2

1.虚拟化介绍

虚拟化是云计算的基础。简单的说，虚拟化使得在一台物理的服务器上可以跑多台虚拟机，虚拟机共享物理机的 CPU、内存、IO 硬件资源，但逻辑上虚拟机之间是相互隔离的。

物理机我们一般称为宿主机（Host），宿主机上面的虚拟机称为客户机（Guest）。

那么 Host 是如何将自己的硬件资源虚拟化，并提供给 Guest 使用的呢？
这个主要是通过一个叫做 Hypervisor 的程序实现的。

根据 Hypervisor 的实现方式和所处的位置，虚拟化又分为两种：

• 全虚拟化
• 半虚拟化

全虚拟化：

Hypervisor 直接安装在物理机上，多个虚拟机在 Hypervisor 上运行。Hypervisor 实现方式一般是一个特殊定制的 Linux 系统。Xen 和 VMWare 的 ESXi 都属于这个类型

半虚拟化：

物理机上首先安装常规的操作系统，比如 Redhat、Ubuntu 和 Windows。Hypervisor 作为 OS 上的一个程序模块运行，并对管理虚拟机进行管理。KVM、VirtualBox 和 VMWare Workstation 都属于这个类型

理论上讲：
全虚拟化一般对硬件虚拟化功能进行了特别优化，性能上比半虚拟化要高；
半虚拟化因为基于普通的操作系统，会比较灵活，比如支持虚拟机嵌套。嵌套意味着可以在KVM虚拟机中再运行KVM。

2.kvm介绍

kVM 全称是 Kernel-Based Virtual Machine。也就是说 KVM 是基于 Linux 内核实现的。
KVM有一个内核模块叫 kvm.ko，只用于管理虚拟 CPU 和内存。

那 IO 的虚拟化，比如存储和网络设备则是由 Linux 内核与Qemu来实现。

作为一个 Hypervisor，KVM 本身只关注虚拟机调度和内存管理这两个方面。IO 外设的任务交给 Linux 内核和 Qemu。

大家在网上看 KVM 相关文章的时候肯定经常会看到 Libvirt 这个东西。

Libvirt 就是 KVM 的管理工具。

其实，Libvirt 除了能管理 KVM 这种 Hypervisor，还能管理 Xen，VirtualBox 等。

Libvirt 包含 3 个东西：后台 daemon 程序 libvirtd、API 库和命令行工具 virsh

• libvirtd是服务程序，接收和处理 API 请求；
• API 库使得其他人可以开发基于 Libvirt 的高级工具，比如 virt-manager，这是个图形化的 KVM 管理工具；
• virsh 是我们经常要用的 KVM 命令行工具

3. kvm部署

环境说明：

系统类型	IP
centos7	192.168.139.128

3.1 kvm安装

部署前请确保你的CPU虚拟化功能已开启。分为两种情况：

• 虚拟机要关机设置CPU虚拟化
• 物理机要在BIOS里开启CPU虚拟化

//关闭防火墙与SELINUX
[root@localhost ~]# systemctl status firewalld
● firewalld.service - firewalld - dynamic firewall daemon
   Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; vendor preset: enabled)
   Active: inactive (dead)
     Docs: man:firewalld(1)
[root@localhost ~]# getenforce 
Disabled

//验证CPU是否支持KVM；如果结果中有vmx（Intel）或svm(AMD)字样，就说明CPU的支持的
[root@localhost ~]# egrep -o 'vmx|svm' /proc/cpuinfo
vmx
vmx

//kvm安装
[root@localhost ~]# yum -y install qemu-kvm qemu-kvm-tools qemu-img virt-manager libvirt libvirt-python libvirt-client virt-install virt-viewer bridge-utils libguestfs-tools

//将KVM服务器的网卡配置成桥接模式
[root@localhost ~]# cd /etc/sysconfig/network-scripts/
[root@localhost network-scripts]# ls
ifcfg-ens33  ifdown-ppp       ifup-ib      ifup-Team
ifcfg-lo     ifdown-routes    ifup-ippp    ifup-TeamPort
......
[root@localhost network-scripts]# cp ifcfg-ens33 ifcfg-br0
[root@localhost network-scripts]# vim ifcfg-br0    //配置br0
[root@localhost network-scripts]# cat ifcfg-br0 
TYPE=Bridge
BOOTPROTO=static
NAME=br0
DEVICE=br0
NM_CONTROLLED=no
ONBOOT=yes
IPADDR=192.168.139.128
NETMASK=255.255.255.0
GATEWAY=192.168.139.2
DNS1=192.168.139.2
[root@localhost network-scripts]# vim ifcfg-ens33    //配置ens33
[root@localhost network-scripts]# cat ifcfg-ens33 
TYPE=Ethernet
BOOTPROTO=static
NAME=ens33
DEVICE=ens33
ONBOOT=yes
BRIDGE=br0
NM_CONTROLLED=no

//重启网络
[root@localhost ~]# systemctl restart network
[root@localhost ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UP group default qlen 1000
    link/ether 00:0c:29:15:7d:cc brd ff:ff:ff:ff:ff:ff
    inet6 fe80::20c:29ff:fe15:7dcc/64 scope link 
       valid_lft forever preferred_lft forever
3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 00:0c:29:15:7d:cc brd ff:ff:ff:ff:ff:ff
    inet 192.168.139.128/24 brd 192.168.139.255 scope global br0
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe15:7dcc/64 scope link 
       valid_lft forever preferred_lft forever
       
//启动服务
[root@localhost ~]# systemctl enable --now libvirtd

//验证安装结果
[root@localhost ~]# lsmod|grep kvm
kvm_intel             188644  0 
kvm                   621480  1 kvm_intel
irqbypass              13503  1 kvm

//测试并验证安装结果
[root@localhost ~]# virsh -c qemu:///system list
 Id    Name                           State
----------------------------------------------------

[root@localhost ~]# virsh --version
4.5.0
[root@localhost ~]# ln -s /usr/libexec/qemu-kvm /usr/bin/qemu-kvm

//查看网桥信息
[root@localhost ~]# brctl show
bridge name	bridge id		STP enabled	interfaces
br0		8000.000c29157dcc	no		ens33
virbr0		8000.525400aad4a0	yes		virbr0-nic

3.2 kvm web管理界面安装

kvm 的 web 管理界面是由 webvirtmgr 程序提供的。

//安装依赖包
[root@localhost ~]# yum -y install epel-release git python-pip libvirt-python libxml2-python python-websockify supervisor nginx python-devel

//升级pip
[root@localhost ~]# pip install --upgrade pip

//从github上下载webvirtmgr代码
[root@localhost ~]# cd /usr/local/src/
[root@localhost src]# git clone git://github.com/retspen/webvirtmgr.git
Cloning into 'webvirtmgr'...
remote: Enumerating objects: 5614, done.
remote: Total 5614 (delta 0), reused 0 (delta 0), pack-reused 5614
Receiving objects: 100% (5614/5614), 2.98 MiB | 364.00 KiB/s, done.
Resolving deltas: 100% (3602/3602), done.

//安装webvirtmgr
[root@localhost src]# cd webvirtmgr/
[root@localhost webvirtmgr]# pip install -r requirements.txt -i https://pypi.tuna.tsinghua.edu.cn/simple

//检查sqlite3是否安装
[root@localhost webvirtmgr]# python
Python 2.7.5 (default, Apr  2 2020, 13:16:51) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-39)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sqlite3    //没有报错说明已安装
>>> exit()

//初始化帐号信息
[root@localhost webvirtmgr]# python manage.py syncdb
WARNING:root:No local_settings file found.
Creating tables ...
Creating table auth_permission
Creating table auth_group_permissions
Creating table auth_group
Creating table auth_user_groups
Creating table auth_user_user_permissions
Creating table auth_user
Creating table django_content_type
Creating table django_session
Creating table django_site
Creating table servers_compute
Creating table instance_instance
Creating table create_flavor

You just installed Django's auth system, which means you don't have any superusers defined.
Would you like to create one now? (yes/no): yes    //是否创建超级管理员账号
Username (leave blank to use 'root'): admin    //指定超级管理员用户名，默认留空为root
Email address: [e-mail]    //邮箱
Password:     //设置超级管理员密码
Password (again):     //再次输入超级管理员密码
Superuser created successfully.
Installing custom SQL ...
Installing indexes ...
Installed 6 object(s) from 1 fixture(s)


//拷贝web网页至指定目录
[root@localhost webvirtmgr]# mkdir /var/www
[root@localhost webvirtmgr]# cp -r /usr/local/src/webvirtmgr /var/www/
[root@localhost webvirtmgr]# chown -R nginx.nginx /var/www/webvirtmgr/

//生成密钥
[root@localhost ~]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
Created directory '/root/.ssh'.
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:oluY0u/PvZ092B8sSe2SD3ZnKPmEBmBAXYEeXk9QncM [e-mail]
The key's randomart image is:
+---[RSA 2048]----+
|     .o. o++.o . |
|       .+ . . E  |
|       ooo o   . |
|       .o.  . .  |
|      . S .  . . |
|   . + .   ..o=. |
|  . = .     =Xo=o|
|   . + . . oo*O.o|
|    ..o.o o.o o+.|
+----[SHA256]-----+
//由于这里webvirtmgr和kvm服务部署在同一台机器，所以这里本地信任。如果kvm部署在其他机器，那么这个是它的ip
[root@localhost ~]# ssh-copy-id 192.168.139.128
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.139.128 (192.168.139.128)' can't be established.
ECDSA key fingerprint is SHA256:UqJZZgVxqVowpEr0URJzQHh4bWmhb/455DNux++yiys.
ECDSA key fingerprint is MD5:92:5d:3f:92:0f:5e:8c:a4:5a:01:4a:e7:b2:17:4f:e1.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.139.128's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh '192.168.139.128'"
and check to make sure that only the key(s) you wanted were added.

//配置端口转发
[root@localhost ~]# ssh 192.168.139.128 -L localhost:8000:localhost:8000 -L localhost:6080:localhost:60
Last login: Mon Aug  3 23:29:49 2020 from 192.168.139.1
[root@localhost ~]# ss -antl
State      Recv-Q Send-Q Local Address:Port               Peer Address:Port              
LISTEN     0      100    127.0.0.1:25                   *:*                  
LISTEN     0      128    127.0.0.1:6080                 *:*                  
LISTEN     0      128    127.0.0.1:8000                 *:*                  
LISTEN     0      5      192.168.122.1:53                   *:*                  
LISTEN     0      128      *:22                   *:*                  
LISTEN     0      100      [::1]:25                    [::]:*                  
LISTEN     0      128      [::1]:6080                  [::]:*                  
LISTEN     0      128      [::1]:8000                  [::]:*                  
LISTEN     0      128       [::]:22                    [::]:*



//配置nginx
[root@localhost ~]# vim /etc/nginx/nginx.conf
//清空原有内容并添加以下内容
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;

include /usr/share/nginx/modules/*.conf;

events {
    worker_connections 1024;
}

http {
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile            on;
    tcp_nopush          on;
    tcp_nodelay         on;
    keepalive_timeout   65;
    types_hash_max_size 2048;

    include             /etc/nginx/mime.types;
    default_type        application/octet-stream;

    include /etc/nginx/conf.d/*.conf;

    server {
        listen       80;
        server_name  localhost;

        include /etc/nginx/default.d/*.conf;

        location / {
            root html;
            index index.html index.htm;
        }

        error_page 404 /404.html;
            location = /40x.html {
        }

        error_page 500 502 503 504 /50x.html;
            location = /50x.html {
        }
    }
}

[root@localhost ~]# vim /etc/nginx/conf.d/webvirtmgr.conf
//添加以下内容
server {
    listen 80 default_server;

    server_name $hostname;
    #access_log /var/log/nginx/webvirtmgr_access_log;

    location /static/ {
        root /var/www/webvirtmgr/webvirtmgr;
        expires max;
    }

    location / {
        proxy_pass http://127.0.0.1:8000;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-for $proxy_add_x_forwarded_for;
        proxy_set_header Host $host:$server_port;
        proxy_set_header X-Forwarded-Proto $remote_addr;
        proxy_connect_timeout 600;
        proxy_read_timeout 600;
        proxy_send_timeout 600;
        client_max_body_size 1024M;
    }
}

//确保bind绑定的是本机的8000端口
[root@localhost ~]# vim /var/www/webvirtmgr/conf/gunicorn.conf.py
.....
bind = '0.0.0.0:8000'     //确保此处绑定的是本机的8000端口，这个在nginx配置中定义了，被代理的端口
backlog = 2048
.....

//启动nginx并设置开机自启
[root@localhost ~]# systemctl enable --now nginx
Created symlink from /etc/systemd/system/multi-user.target.wants/nginx.service to /usr/lib/systemd/system/nginx.service.
[root@localhost ~]# ss -antl
State      Recv-Q Send-Q Local Address:Port               Peer Address:Port              
LISTEN     0      100    127.0.0.1:25                   *:*                  
LISTEN     0      128    127.0.0.1:6080                 *:*                  
LISTEN     0      128    127.0.0.1:8000                 *:*                  
LISTEN     0      128      *:80                   *:*                  
LISTEN     0      5      192.168.122.1:53                   *:*                  
LISTEN     0      128      *:22                   *:*                  
LISTEN     0      100      [::1]:25                    [::]:*                  
LISTEN     0      128      [::1]:6080                  [::]:*                  
LISTEN     0      128      [::1]:8000                  [::]:*                  
LISTEN     0      128       [::]:22                    [::]:*



//设置supervisor
[root@localhost ~]# vim /etc/supervisord.conf
//在文件最后添加以下内容
[program:webvirtmgr]
command=/usr/bin/python2 /var/www/webvirtmgr/manage.py run_gunicorn -c /var/www/webvirtmgr/conf/gunicorn.conf.py
directory=/var/www/webvirtmgr
autostart=true
autorestart=true
logfile=/var/log/supervisor/webvirtmgr.log
log_stderr=true
user=nginx

[program:webvirtmgr-console]
command=/usr/bin/python2 /var/www/webvirtmgr/console/webvirtmgr-console
directory=/var/www/webvirtmgr
autostart=true
autorestart=true
stdout_logfile=/var/log/supervisor/webvirtmgr-console.log
redirect_stderr=true
user=nginx


//启动supervisor并设置开机自启
[root@localhost ~]# systemctl enable --now supervisord
Created symlink from /etc/systemd/system/multi-user.target.wants/supervisord.service to /usr/lib/systemd/system/supervisord.service.

//配置nginx用户
[root@localhost ~]# su - nginx -s /bin/bash
-bash-4.2$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/var/lib/nginx/.ssh/id_rsa): 
Created directory '/var/lib/nginx/.ssh'.
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /var/lib/nginx/.ssh/id_rsa.
Your public key has been saved in /var/lib/nginx/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:z2XuG/p5qsS88DEgV/LY6ZG8z518IcmxgiTcCvMweqo [e-mail]
The key's randomart image is:
+---[RSA 2048]----+
|                 |
|                 |
|      . o .      |
|     = o X o .   |
|    . B S O + +  |
|   . . = O B = . |
|    o   . @ + . .|
|   .     + O =...|
| E.       =oO++. |
+----[SHA256]-----+
-bash-4.2$ touch ~/.ssh/config && echo -e "StrictHostKeyChecking=no\nUserKnownHostsFile=/dev/null" >> ~/.ssh/config
-bash-4.2$ chmod 0600 ~/.ssh/config

-bash-4.2$ ssh-copy-id root@192.168.139.128
/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/var/lib/nginx/.ssh/id_rsa.pub"
/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
Warning: Permanently added '192.168.139.128' (ECDSA) to the list of known hosts.
root@192.168.139.128's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'root@192.168.139.128'"
and check to make sure that only the key(s) you wanted were added.

-bash-4.2$ exit
logout

[root@localhost ~]# vim /etc/polkit-1/localauthority/50-local.d/50-libvirt-remote-access.pkla
//添加以下内容 
[Remote libvirt SSH access]
Identity=unix-user:root
Action=org.libvirt.unix.manage
ResultAny=yes
ResultInactive=yes
ResultActive=yes

[root@localhost ~]# chown -R root.root /etc/polkit-1/localauthority/50-local.d/50-libvirt-remote-access.pkla
[root@localhost ~]# systemctl restart nginx
[root@localhost ~]# systemctl restart libvirtd

3.3 kvm web界面管理

通过ip地址在浏览器上访问kvm

3.3.1 kvm连接管理

创建SSH连接：

3.3.2 kvm存储管理

创建存储：

将准备好的系统镜像放入/storage目录

[root@localhost ~]# mv CentOS-7-x86_64-Minimal-1908.iso /storage/
[root@localhost ~]# ls /storage/
CentOS-7-x86_64-Minimal-1908.iso

创建系统安装镜像

3.3.3 kvm网络管理

添加桥接网络

3.3.4 实例管理

实例(虚拟机)创建

虚拟机插入光盘

设置在 web 上访问虚拟机的密码

启动虚拟机

虚拟机安装

选择Install CentOS 7进行安装

安装过程请自行百度看到以下界面表示系统安装成功

4.故障案例

4.1 案例1

第一次通过web访问kvm时可能会一直访问不了，一直转圈，而命令行界面一直报错(too many open files)

此时需要对nginx进行配置

[root@localhost ~]# vim /etc/nginx/nginx.conf
....此处省略N行
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
worker_rlimit_nofile 655350;    //添加此行配置

# Load dynamic modules. See /usr/share/nginx/README.dynamic.
....此处省略N行

[root@localhost ~]# systemctl restart nginx

然后对系统参数进行设置

[root@localhost ~]# vim /etc/security/limits.conf
....此处省略N行
# End of file
* soft nofile 655350
* hard nofile 655350

到此问题即可解决

4.2 案例2

web界面配置完成后可能会出现以下错误界面

解决方法是安装novnc并通过novnc_server启动一个vnc

[root@localhost ~]# yum -y in[root@localhost ~]# chmod +x /etc/rc.d/rc.local
[root@localhost ~]# ll /etc/rc.local 
lrwxrwxrwx. 1 root root 13 Jul 31 13:02 /etc/rc.local -> rc.d/rc.local
[root@localhost ~]# ll /etc/rc.d/rc.local 
-rwxr-xr-x. 1 root root 473 Aug  8  2019 /etc/rc.d/rc.local
[root@localhost ~]# vim /etc/rc.d/rc.local
//在最后面添加以下内容
nohup novnc_server 192.168.139.128:5920 &

[root@localhost ~]# source /etc/rc.d/rc.local
[root@localhost ~]# nohup: ignoring input and appending output to ‘nohup.out’    //已成功后台运行

做完以上操作后再次访问即可正常访问