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能够跑多台虚拟机,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。
物理机咱们通常称为宿主机(Host),宿主机上面的虚拟机称为客户机(Guest)。
那么 Host 是如何将本身的硬件资源虚拟化,并提供给 Guest 使用的呢?
这个主要是经过一个叫作 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html
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 实现方式通常是一个特殊定制的 Linux 系统。Xen 和 VMWare 的 ESXi 都属于这个类型python
半虚拟化:
物理机上首先安装常规的操做系统,好比 Redhat、Ubuntu 和 Windows。Hypervisor 做为 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linux
理论上讲:
全虚拟化通常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;
半虚拟化由于基于普通的操做系统,会比较灵活,好比支持虚拟机嵌套。嵌套意味着能够在KVM虚拟机中再运行KVM。nginx
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,好比存储和网络设备则是由 Linux 内核与Qemu来实现。
做为一个 Hypervisor,KVM 自己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。
你们在网上看 KVM 相关文章的时候确定常常会看到 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 virshc++
环境说明git
系统类型 | RHEL7 |
---|---|
IP | 192.168.100.100 |
部署前请确保你的CPU虚拟化功能已开启。分为两种状况:github
虚拟机开启虚拟化步骤web
//关闭防火墙与SELINUX [root@kvm ~]# systemctl stop firewalld [root@kvm ~]# systemctl disable firewalld Removed symlink /etc/systemd/system/multi-user.target.wants/firewalld.service. Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service. [root@kvm ~]# setenforce 0 [root@kvm ~]# sed -ri 's/^(SELINUX=).*/\1disabled/g' /etc/selinux/config [root@localhost ~]# reboot //配置网络源 [root@kvm yum.repos.d]# curl -o /etc/yum.repos.d/CentOS7-Base-163.repo http://mirrors.163.com/.help/CentOS7-Base-163.repo [root@kvm yum.repos.d]# sed -i 's/\$releasever/7/g' /etc/yum.repos.d/CentOS7-Base-163.repo [root@kvm yum.repos.d]# sed -i 's/^enabled=.*/enabled=1/g' /etc/yum.repos.d/CentOS7-Base-163.repo [root@kvm yum.repos.d]# yum -y install epel-release ……下载过程略 //下载工具包 [root@kvm ~]# yum install -y vim wget net-tools unzip zip gcc gcc-c++ ……下载过程略 //验证CPU是否支持KVM;若是结果中有vmx(Intel)或svm(AMD)字样,就说明CPU的支持的 [root@kvm ~]# egrep -o 'vmx|svm' /proc/cpuinfo vmx vmx //kvm安装 [root@kvm ~]# 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 ……下载过程略 //下面操做可作可不作(本身根据状况而定!!!) //由于虚拟机中网络,咱们通常都是和公司的其余服务器是同一个网段,因此咱们须要把 KVM服务器的网卡配置成桥接模式。这样的话KVM的虚拟机就能够经过该桥接网卡和公司内部 其余服务器处于同一网段 //此处个人网卡是ens33,因此用br0来桥接ens33网卡 [root@kvm ~]# cd /etc/sysconfig/network-scripts/ [root@kvm 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 [root@kvm network-scripts]# cp ifcfg-ens33 ifcfg-br0 [root@kvm network-scripts]# cat ifcfg-br0 TYPE=Bridge DEVICE=br0 NM_CONTROLLED=no BOOTPROTO=static NAME=br0 ONBOOT=yes IPADDR=192.168.100.100 NETMASK=255.255.255.0 GATEWAY=192.168.100.2 DNS1=192.168.100.2 [root@kvm 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@kvm ~]# systemctl restart network [root@kvm ~]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UP qlen 1000 link/ether 00:0c:29:0f:a6:60 brd ff:ff:ff:ff:ff:ff inet6 fe80::20c:29ff:fe0f:a660/64 scope link valid_lft forever preferred_lft forever 3: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000 link/ether 00:0c:29:0f:a6:60 brd ff:ff:ff:ff:ff:ff inet 192.168.100.100/24 brd 192.168.100.255 scope global br0 valid_lft forever preferred_lft forever inet6 fe80::20c:29ff:fe0f:a660/64 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 52:54:00:3b:2c:6a brd ff:ff:ff:ff:ff:ff inet 192.168.206.1/24 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 52:54:00:3b:2c:6a brd ff:ff:ff:ff:ff:ff //操做今后处开始 //启动服务 [root@kvm ~]# systemctl start libvirtd [root@kvm ~]# systemctl enable libvirtd //验证安装结果 [root@kvm ~]# 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 [root@kvm ~]# virsh -c qemu:///system list Id Name State ---------------------------------------------------- [root@kvm ~]# virsh --version 4.5.0 [root@kvm ~]# virt-install --version 1.5.0 [root@kvm ~]# ln -s /usr/libexec/qemu-kvm /usr/bin/qemu-kvm [root@kvm ~]# ll /usr/bin/qemu-kvm lrwxrwxrwx 1 root root 21 Oct 18 10:57 /usr/bin/qemu-kvm -> /usr/libexec/qemu-kvm [root@kvm ~]# lsmod |grep kvm kvm_intel 170086 0 kvm 566340 1 kvm_intel irqbypass 13503 1 kvm // 查看网桥信息 [root@kvm ~]# brctl show bridge name bridge id STP enabled interfaces br0 8000.000c294c50b4 no ens33 virbr0 8000.52540060a8ea yes virbr0-nic
设置完成后执行下条命令
[```
root@wan ~]# virt-managersql
会弹出下图:
若是出现乱码则将语言改成英文[root@kvm ~]# LANG=endjango

# 建立一个新磁盘 [root@kvm ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 20G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 19G 0 part ├─rhel-root 253:0 0 17G 0 lvm / └─rhel-swap 253:1 0 2G 0 lvm [SWAP] sdb 8:16 0 20G 0 disk # 分区 所有分为一个主分区 [root@kvm ~]# fdisk /dev/sdb 欢迎使用 fdisk (util-linux 2.23.2)。 更改将停留在内存中,直到您决定将更改写入磁盘。 使用写入命令前请三思。 Device does not contain a recognized partition table 使用磁盘标识符 0x3e429af0 建立新的 DOS 磁盘标签。 命令(输入 m 获取帮助):n Partition type: p primary (0 primary, 0 extended, 4 free) e extended Select (default p): Using default response p 分区号 (1-4,默认 1): 起始 扇区 (2048-41943039,默认为 2048): 将使用默认值 2048 Last 扇区, +扇区 or +size{K,M,G} (2048-41943039,默认为 41943039): 将使用默认值 41943039 分区 1 已设置为 Linux 类型,大小设为 20 GiB 命令(输入 m 获取帮助):w The partition table has been altered! Calling ioctl() to re-read partition table. 正在同步磁盘。 [root@kvm ~]# partprobe # 格式化磁盘 [root@kvm ~]# mkfs.ext4 /dev/sdb1 # 建立挂载点目录并挂载 [root@kvm ~]# mkdir /storage [root@kvm ~]# blkid |grep sdb1 /dev/sdb1: UUID="f11ae26e-c529-42d1-8f0f-21cd5a062ac4" TYPE="ext4" [root@kvm ~]# echo 'UUID="f11ae26e-c529-42d1-8f0f-21cd5a062ac4" /storage ext4 defaults 0 0' >>/etc/fstab [root@kvm ~]# mount -a [root@kvm ~]# df -Th 文件系统 类型 容量 已用 可用 已用% 挂载点 /dev/mapper/rhel-root xfs 17G 6.0G 12G 36% / devtmpfs devtmpfs 901M 0 901M 0% /dev tmpfs tmpfs 912M 0 912M 0% /dev/shm tmpfs tmpfs 912M 8.7M 903M 1% /run tmpfs tmpfs 912M 0 912M 0% /sys/fs/cgroup /dev/sda1 xfs 1014M 144M 871M 15% /boot tmpfs tmpfs 183M 0 183M 0% /run/user/0 /dev/sdb1 ext4 20G 45M 19G 1% /storage
kvm 的 web 管理界面是由 webvirtmgr 程序提供的。
//安装依赖包 [root@kvm ~]# yum -y install git python-pip libvirt-python libxml2-python python-websockify supervisor nginx python-devel ……下载过程略 //升级pip [root@kvm ~]# pip install --upgrade pip ……过程略 //从github上下载webvirtmgr代码 [root@kvm ~]# cd /usr/src/ [root@kvm src]# git clone git://github.com/retspen/webvirtmgr.git Cloning into 'webvirtmgr'... remote: Enumerating objects: 5730, done. remote: Total 5730 (delta 0), reused 0 (delta 0), pack-reused 5730 Receiving objects: 100% (5730/5730), 3.01 MiB | 39.00 KiB/s, done. Resolving deltas: 100% (3688/3688), done. //安装webvirtmgr [root@kvm src]# cd webvirtmgr/ [root@kvm webvirtmgr]# pip install -r requirements.txt Collecting django==1.5.5 (from -r requirements.txt (line 1)) Downloading https://files.pythonhosted.org/packages/38/49/93511c5d3367b6b21fc2995a0e53399721afc15e4cd6eb57be879ae13ad4/Django-1.5.5.tar.gz (8.1MB) 57% |██████████████████▌ | 4.7MB 38kB/s eta 0:01:28 .....过程略 //检查sqlite3是否安装 [root@kvm webvirtmgr]# python Python 2.7.5 (default, May 3 2017, 07:55:04) [GCC 4.8.5 20150623 (Red Hat 4.8.5-14)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import sqlite3 >>> exit() //初始化账号信息 [root@kvm 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 //问你是否建立超级管理员账号 Username (leave blank to use 'root'): //指定超级管理员账号用户名,默认留空为root Email address: sean1002@126.com //设置超级管理员邮箱 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@kvm ~]# mkdir /var/www [root@kvm ~]# cp -r /usr/local/src/webvirtmgr /var/www/ [root@kvm ~]# chown -R nginx.nginx /var/www/webvirtmgr/ //生成密钥(下面选择直接回车) [root@kvm ~]# 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:CQoZtso2M5Uo39lKvjZboncqakQ69iJt5wnjiJKZNhw root@kvm The key's randomart image is: +---[RSA 2048]----+ | o | | ..+. | |..+o . | |o+.o + . . | |+*. = . S | |+E+o . | |+*= + . | |BO+===. | |Oo=**= | +----[SHA256]-----+ //因为这里webvirtmgr和kvm服务部署在同一台机器,因此这里本地信任。若是kvm部署在其余机器,那么这个是它的ip [root@kvm ~]# ssh-copy-id 192.168.206.129 /usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub" The authenticity of host '192.168.206.129 (192.168.206.129)' can't be established. ECDSA key fingerprint is SHA256:UszC1ZeHM7xw/uefVkJoXW6XgRw+Jl51tAXLjFERclE. ECDSA key fingerprint is MD5:b3:f1:02:b8:01:8e:53:a7:87:09:c0:75:24:4c:ad:88. 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@192.168.206.129's password: //输入你的root密码 Number of key(s) added: 1 Now try logging into the machine, with: "ssh '192.168.206.129'" and check to make sure that only the key(s) you wanted were added. //配置端口转发 [root@kvm ~]# ssh 192.168.206.129 -L localhost:8000:localhost:8000 -L localhost:6080:localhost:60 Last login: Thu Oct 18 08:26:40 2018 from 192.168.160.36 [root@kvm ~]# 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 [root@kvm ~]# vim /etc/nginx/nginx.conf ....... ....... ....... include /etc/nginx/conf.d/*.conf; //改为下面的内容 server { listen 80; server_name localhost; root /usr/share/nginx/html; # Load configuration files for the default server block. include /etc/nginx/default.d/*.conf; ....... ....... ....... [root@kvm ~]# vim /etc/nginx/conf.d/webvirtmgr.conf //添加如下内容 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@kvm ~]# 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 ..... ..... //重启nginx [root@kvm ~]# systemctl restart nginx [root@kvm ~]# 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 [root@kvm ~]# vim /etc/supervisord.conf .....此处省略上面的内容,在文件最后加上如下内容 [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@kvm ~]# systemctl start supervisord [root@kvm ~]# systemctl enable supervisord Created symlink from /etc/systemd/system/multi-user.target.wants/supervisord.service to /usr/lib/systemd/system/supervisord.service. [root@kvm ~]# 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 Thu 2018-10-18 11:59:33 CST; 25s ago Main PID: 17918 (supervisord) CGroup: /system.slice/supervisord.service └─17918 /usr/bin/python /usr/bin/supervisord -c /etc/supervisord.conf Oct 18 11:59:33 kvm systemd[1]: Starting Process Monitoring and Control Daemon... Oct 18 11:59:33 kvm systemd[1]: Started Process Monitoring and Control Daemon. [root@kvm webvirtmgr]# 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 *:8000 *:* LISTEN 0 100 *:6080 *:* LISTEN 0 128 :::111 :::* LISTEN 0 128 :::22 :::* LISTEN 0 100 ::1:25 :::* // 配置nginx用户 [root@kvm home]# 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:rdbmW/YIXxAJBzPsd9q9eKHPjWtSZ5EQC5li3tkczYI nginx@localhost.localdomain The key's randomart image is: +---[RSA 2048]----+ | .=o=.+ | | o.E.=.o | | o.o *.+ .| | o.o.+.o | | S ...+ ..| | o ..o.+| | o + o.+oo| | . o =.*o+.| | o.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@192.168.206.129 /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 '192.168.160.109' (ECDSA) to the list of known hosts. root@192.168.206.129's password: Number of key(s) added: 1 Now try logging into the machine, with: "ssh 'root@192.168.160.109'" and check to make sure that only the key(s) you wanted were added. -bash-4.2$ exit logout [root@kvm ~]# 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 [root@kvm ~]# chown -R root.root /etc/polkit-1/localauthority/50-local.d/50-libvirt-remote-access.pkla [root@kvm ~]# systemctl restart nginx [root@kvm ~]# systemctl restart libvirtd
经过ip地址在浏览器上访问kvm。
1. 对nginx进行配置
[root@localhost ~]# vim /etc/nginx/nginx.conf 。。。。。 。。。。。 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. 。。。。。 。。。。。 [root@localhost ~]# systemctl restart nginx
二、而后对系统参数进行设置
[root@localhost ~]# vim /etc/security/limits.conf 。。。。。 。。。。。 # End of file //添加下面内容 * soft nofile 655350 * hard nofile 655350
而后就能够经过web对kvm进行访问了。
- 故障现象:
在web界面完成配置,启动时没法启动
解决办法:
[root@localhost ~]# yum -y install novnc [root@localhost ~]# chmod +x /etc/rc.d/rc.local [root@localhost ~]# chmod +x /etc/rc.local [root@localhost ~]# vim /etc/rc.d/rc.local ....... ....... # that this script will be executed during boot. touch /var/lock/subsys/local //添加下面这行(ip填本机ip) nohup novnc_server 192.168.206.129:5920 & [root@localhost ~]# . /etc/rc.d/rc.local
完成后在从新启动便可