kvm虚拟化
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 |
|---|---|
| rhel7 | 192.168.26.10 |
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
[[email protected] ~]# systemctl stop firewalld
[[email protected] ~]# systemctl disable firewalld
Removed symlink /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
[[email protected] ~]# setenforce 0
[[email protected] ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config
[[email protected] ~]# reboot
//配置网络源
[[email protected] yum.repos.d]# curl -o /etc/yum.repos.d/CentOS7-Base-163.repo http://mirrors.163.com/.help/CentOS7-Base-163.repo
[[email protected] ~]# sed -i 's/\$releasever/7/g' /etc/yum.repos.d/CentOS7-Base-163.repo
[[email protected] ~]# sed -i 's/^enabled=.*/enabled=1/g' /etc/yum.repos.d/CentOS7-Base-163.repo
[[email protected] ~]# yum -y install epel-release vim wget net-tools unzip zip gcc gcc-c++
安装过程略.....
//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
[[email protected] ~]# egrep -o 'vmx|svm' /proc/cpuinfo
vmx
vmx
vmx
vmx
//kvm安装
[[email protected] ~]# 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
安装过程略......
//因为虚拟机中网络，我们一般都是和公司的其他服务器是同一个网段，所以我们需要把 \
KVM服务器的网卡配置成桥接模式。这样的话KVM的虚拟机就可以通过该桥接网卡和公司内部 \
其他服务器处于同一网段
//此处我的网卡是ens33，所以用br0来桥接ens33网卡
[[email protected] ~]# cd /etc/sysconfig/network-scripts/
[[email protected] network-scripts]# ls
ifcfg-ens33 ifdown-isdn ifup ifup-plip ifup-tunnel
ifcfg-lo ifdown-post ifup-aliases ifup-plusb
.....此处内容省略
[[email protected] network-scripts]# cp ifcfg-ens33 ifcfg-br0
[[email protected] network-scripts]# cat ifcfg-br0
TYPE=Bridge
DEVICE=br0
NM_CONTROLLED=no
BOOTPROTO=static
NAME=br0
ONBOOT=yes
IPADDR=192.168.160.109
NETMASK=255.255.255.0
GATEWAY=192.168.160.1
DNS1=114.114.114.114
DNS2=8.8.8.8
[[email protected] network-scripts]# cat ifcfg-ens33
TYPE=Ethernet
BOOTPROTO=static
NAME=ens33
DEVICE=ens33
ONBOOT=yes
BRIDGE=br0
NM_CONTROLLED=no
//重启网络
[[email protected] ~]# systemctl restart network
[[email protected] ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
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: ens32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UP qlen 1000
link/ether 00:0c:29:5a:8b:0e brd ff:ff:ff:ff:ff:ff
3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
link/ether 00:0c:29:5a:8b:0e brd ff:ff:ff:ff:ff:ff
inet 192.168.26.100/24 brd 192.168.26.255 scope global br0
valid_lft forever preferred_lft forever
inet6 fe80::71c7:a6ba:1fe7:1648/64 scope link
valid_lft forever preferred_lft forever
4: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN qlen 1000
link/ether 52:54:00:8f:4c:09 brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever
5: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN qlen 1000
link/ether 52:54:00:8f:4c:09 brd ff:ff:ff:ff:ff:ff
//启动服务
[[email protected] ~]# systemctl start libvirtd
[[email protected] ~]# systemctl enable libvirtd
//验证安装结果
[[email protected] ~]# lsmod|grep kvm
kvm_intel 170086 0
kvm 566340 1 kvm_intel
irqbypass 13503 1 kvm
//测试并验证安装结果
[[email protected] ~]# virsh -c qemu:///system list
Id Name State
----------------------------------------------------
[[email protected] ~]# virsh --version
3.9.0
[[email protected] ~]# virt-install --version
1.4.3
[[email protected] ~]# ln -s /usr/libexec/qemu-kvm /usr/bin/qemu-kvm
[[email protected] ~]# ll /usr/bin/qemu-kvm
lrwxrwxrwx 1 root root 21 Oct 18 10:57 /usr/bin/qemu-kvm -> /usr/libexec/qemu-kvm
[[email protected] ~]# lsmod |grep kvm
kvm_intel 170086 0
kvm 566340 1 kvm_intel
irqbypass 13503 1 kvm
//查看网桥信息
[[email protected] ~]# brctl show
bridge name bridge id STP enabled interfaces
br0 8000.000c294c50b4 no ens32
virbr0 8000.52540060a8ea 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。
装依赖包
[[email protected] ~]# yum -y install git python-pip libvirt-python libxml2-python python-websockify supervisor nginx python-devel
//升级pip
[[email protected] ~]# pip install --upgrade pip
Collecting pip
Downloading https://files.pythonhosted.org/packages/d8/f3/413bab4ff08e1fc4828dfc59996d721917df8e8583ea85385d51125dceff/pip-19.0.3-py2.py3-none-any.whl (1.4MB)
100% |████████████████████████████████| 1.4MB 185kB/s
Installing collected packages: pip
Found existing installation: pip 8.1.2
Uninstalling pip-8.1.2:
Successfully uninstalled pip-8.1.2
Successfully installed pip-19.0.3
//安装webvirtmgr
[[email protected] src]# cd webvirtmgr/
[[email protected] webvirtmgr]# pip install -r requirements.txt
DEPRECATION: Python 2.7 will reach the end of its life on January 1st, 2020. Please upgrade your Python as Python 2.7 won't be maintained after that date. A future version of pip will drop support for Python 2.7.
Collecting django==1.5.5 (from -r requirements.txt (line 1))
Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x7f9c23b0c5d0>: Failed to establish a new connection: [Errno 101] Network is unreachable',)': /packages/38/49/93511c5d3367b6b21fc2995a0e53399721afc15e4cd6eb57be879ae13ad4/Django-1.5.5.tar.gz
Downloading https://files.pythonhosted.org/packages/38/49/93511c5d3367b6b21fc2995a0e53399721afc15e4cd6eb57be879ae13ad4/Django-1.5.5.tar.gz (8.1MB)
100% |████████████████████████████████| 8.1MB 183kB/s
Collecting gunicorn==19.5.0 (from -r requirements.txt (line 2))
Downloading https://files.pythonhosted.org/packages/f9/4e/f4076a1a57fc1e75edc0828db365cfa9005f9f6b4a51b489ae39a91eb4be/gunicorn-19.5.0-py2.py3-none-any.whl (113kB)
100% |████████████████████████████████| 122kB 248kB/s
Collecting lockfile>=0.9 (from -r requirements.txt (line 5))
Downloading https://files.pythonhosted.org/packages/c8/22/9460e311f340cb62d26a38c419b1381b8593b0bb6b5d1f056938b086d362/lockfile-0.12.2-py2.py3-none-any.whl
Installing collected packages: django, gunicorn, lockfile
Running setup.py install for django ... done
Successfully installed django-1.5.5 gunicorn-19.5.0 lockfile-0.12.2
//检查sqlite3是否安装
[[email protected] webvirtmgr]# python
Python 2.7.5 (default, Oct 30 2018, 23:45:53)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-36)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sqlite3
>>> exit()
//初始化帐号信息
[[email protected] 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
Username (leave blank to use 'root'):
Email address: [email protected]
Password:
Password (again):
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
[[email protected] webvirtmgr]# mkdir /var/www
[[email protected] webvirtmgr]# cp -r /usr/local/src/webvirtmgr /var/www/
[[email protected] webvirtmgr]# chown -R nginx.nginx /var/www/webvirtmgr/
//生成**
[[email protected] ~]# ssh-****** -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
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:KB67wuyLunemF0dbNA1bxKSC8Js5gm0eWixnuJvfLc8 [email protected]
The key's randomart image is:
+---[RSA 2048]----+
| . .*+ |
| o . o+o |
| o ..o. |
| = +.o. |
|+ X B..oS |
| X +.=o |
|oo. oo |
| +=.=+ |
|B==BooE |
+----[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
[[email protected] ~]# ssh-copy-id 192.168.26.100
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.26.100 (192.168.26.100)' can't be established.
ECDSA key fingerprint is SHA256:VRexELvzfF9WjrSWWb+RYdb76ehlN55pqdo2DRsQPH0.
ECDSA key fingerprint is MD5:f3:77:ea:00:7c:41:de:e2:36:b4:9a:bd:23:92:ca:ba.
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
[email protected]'s password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh '192.168.26.100'"
and check to make sure that only the key(s) you wanted were added.
//配置端口转发
[[email protected] ~]# ssh 192.168.26.100 -L localhost:8000:localhost:8000 -L localhost:6080:localhost:60
Last login: Mon Mar 11 04:36:48 2019 from 192.168.26.1
[[email protected] ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:111 *:*
LISTEN 0 5 192.168.122.1:53 *:*
LISTEN 0 128 *:22 *:*
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 :::111 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
LISTEN 0 128 ::1:6080 :::*
LISTEN 0 128 ::1:8000 :::*
//配置nginx
[[email protected] ~]# vim /etc/nginx/nginx.conf
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 {
}
}
}
[[email protected] ~]# vim /etc/nginx/conf.d/webvirtmgr.conf
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
[[email protected] ~]# vim /var/www/webvirtmgr/conf/gunicorn.conf.py
.....此处省略N行
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
.....此处省略N行
//重启nginx
[[email protected] ~]# systemctl restart nginx
[[email protected] ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:111 *:*
LISTEN 0 128 *:80 *:*
LISTEN 0 5 192.168.122.1:53 *:*
LISTEN 0 128 *:22 *:*
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 :::111 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
LISTEN 0 128 ::1:6080 :::*
LISTEN 0 128 ::1:8000 :::*
//设置supervisor
[[email protected] ~]# vim /etc/supervisord.conf
.....此处省略上面的内容，在文件最后加上以下内容
[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
[[email protected] ~]# systemctl start supervisord
[[email protected] ~]# systemctl enable supervisord
Created symlink from /etc/systemd/system/multi-user.target.wants/supervisord.service to /usr/lib/systemd/system/supervisord.service.
[[email protected] ~]# systemctl status supervisord
● supervisord.service - Process Monitoring and Control Daemon
Loaded: loaded (/usr/lib/systemd/system/supervisord.service; enabled; vendor preset: disabled)
Active: active (running) since Mon 2019-03-11 06:43:09 EDT; 13s ago
Main PID: 2928 (supervisord)
CGroup: /system.slice/supervisord.service
├─2928 /usr/bin/python /usr/bin/supervisord -c /etc/supervisord.conf
└─2974 /usr/bin/python2 /var/www/webvirtmgr/manage.py run_gunicorn -c /var/www/webvirtmgr/con...
Mar 11 06:43:08 localhost.localdomain systemd[1]: Starting Process Monitoring and Control Daemon...
Mar 11 06:43:09 localhost.localdomain systemd[1]: Started Process Monitoring and Control Daemon.
[[email protected] ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:111 *:*
LISTEN 0 128 *:80 *:*
LISTEN 0 5 192.168.122.1:53 *:*
LISTEN 0 128 *:22 *:*
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 :::111 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
LISTEN 0 128 ::1:6080 :::*
LISTEN 0 128 ::1:8000 :::*
//配置nginx用户
[[email protected] ~]# cd /home/
[[email protected] home]# mkdir nginx
[[email protected] home]# chown -R nginx.nginx nginx/
[[email protected] home]# chmod -R 700 nginx/
[[email protected] home]# su - nginx -s /bin/bash
-bash-4.2$ ssh-****** -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:hpbr/d2egvefqbKVvdTn4qmhGkok6xK3csgHKLXvgjw [email protected]
The key's randomart image is:
+---[RSA 2048]----+
| |
| |
| |
| . o |
| o .. = S |
|o + .= o o .|
|oo *..o . ..o oo|
|.E*.=o o ..++oo+=|
| .Bo o oooo=BO*o|
+----[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 [email protected]
/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 '192.168.26.100' (ECDSA) to the list of known hosts.
[email protected]'s password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh '[email protected]'"
and check to make sure that only the key(s) you wanted were added.
-bash-4.2$ exit
logout
[[email protected] ~]# vim /etc/polkit-1/localauthority/50-local.d/50-libvirt-remote-access.pkla
[Remote libvirt SSH access]
Identity=unix-user:root
Action=org.libvirt.unix.manage
ResultAny=yes
ResultInactive=yes
ResultActive=yes
[[email protected] ~]# chown -R root.root /etc/polkit-1/localauthority/50-local.d/50-libvirt-remote-access.pkla
[[email protected] ~]# systemctl restart nginx
[[email protected] ~]# systemctl restart libvirtd
kvm web界面管理
通过IP地址在浏览器*问KVM，例如我这里就是：http://192.168.26.100/login通过远程连接软件上传ISO镜像文件至存储目录/var/lib/libvirt/images/
[[email protected] ~]# cd /var/lib/libvirt/images/
[[email protected] images]# ls
[[email protected] images]#
[[email protected] images]# ls
CentOS-7.4-x86_64-DVD-1708.iso
创建系统安装镜像添加成功如下图所示
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
虚拟机插入光盘虚拟机安装