目錄

KVM虛擬化

創建虛擬機

報錯解決

虛擬化介紹

kvm介紹

KVM部署（基于CentOS7）

KVM管理界面安裝

KVM web界面管理

虛擬化介紹

虛擬化：在一臺計算機上虛擬出多個邏輯的計算機，而且每個邏輯計算機
它可以是不同操作系統

虛擬化技術：可以擴大硬件容量，單個cpu模擬出多個cpu并行，
允許一個平臺上同時運行多個操作系統，應用程序都可以在相互獨立
的空間內運行，而且互不影響。

為什么企業使用虛擬化技術

1、節約成本

2、提高效率，物理機我們一般稱為宿主機（Host），宿主機上面的虛擬機稱為客戶機（Guest）。

那么 Host 是如何將自己的硬件資源虛擬化，并提供給 Guest 使用的呢？

這個主要是通過一個叫做 Hypervisor 的程序實現的。

Hypervisor：一種運行在物理服務器硬件與操作系統之間的中間軟件層

可允許多個操作系統和應用來共享硬件資源

根據 Hypervisor 的實現方式和所處的位置，虛擬化又分為兩種：

完全虛擬化：直接在物理機上部署虛擬化，且不需要修改操作系統內核

半虛擬化：需要修改操作系統內核，使其支持虛擬化驅動來實現虛擬化技術

1、完全虛擬化
Hypervisor 直接安裝在物理機上，多個虛擬機在 Hypervisor 上運行。Hypervisor 實現方式一般是一個特殊定制的 Linux 系統。Xen 和 VMWare 的 ESXi 都屬于這個類型

2、半虛擬化

理論上講：

完全虛擬化一般對硬件虛擬化功能進行了特別優化，性能上比半虛擬化要高；

半虛擬化因為基于普通的操作系統，會比較靈活，比如支持虛擬機嵌套。嵌套意味著可以在KVM虛擬機中再運行KVM。

kvm介紹

kVM 全稱是 Kernel-Based Virtual Machine。也就是說 KVM 是基于 Linux 內核實現的。

KVM有一個內核模塊叫 kvm.ko，只用于管理虛擬 CPU 和內存。

那 IO 的虛擬化，比如存儲和網絡設備則是由 Linux 內核與Qemu來實現。

Qemu 是純軟件實現的虛擬化模擬器，幾乎可以模擬任何硬件設備，我們最熟悉的就是能夠模擬一臺能夠獨立運行操作系統的虛擬機，虛擬機認為自己和硬件打交道，但其實是和 Qemu 模擬出來的硬件打交道，Qemu 將這些指令轉譯給真正的硬件。

正因為 Qemu 是純軟件實現的，所有的指令都要經 Qemu 過一手，性能非常低，所以，在生產環境中，大多數的做法都是配合 KVM 來完成虛擬化工作，因為 KVM 是硬件輔助的虛擬化技術，主要負責 比較繁瑣的 CPU 和內存虛擬化，而 Qemu 則負責 I/O 虛擬化，兩者合作各自發揮自身的優勢，相得益彰。

作為一個 Hypervisor，KVM 本身只關注虛擬機調度和內存管理這兩個方面。IO 外設的任務交給 Linux 內核和 Qemu。

Libvirt 就是 KVM 的管理工具。管理虛擬機和虛擬化功能的軟件

其實，Libvirt 除了能管理 KVM 這種 Hypervisor，還能管理 Xen，VirtualBox 等。

Libvirt 包含 3 個東西：后臺 daemon 程序 libvirtd、API 庫和命令行工具 virsh

1、libvirtd是服務程序，接收和處理 API 請求；

2、API 庫使得其他人可以開發基于 Libvirt 的高級工具，比如 virt-manager，這是個圖形化的 KVM 管理工具；

3、virsh 是我們經常要用的 KVM 命令行工具

KVM部署（基于CentOS7）

虛擬機的安裝步驟可以查看我之前centos8.5的安裝，變化倒是不大修改一下對應參數就可以了

環境說明：

系統：CentOS7

ip ：192.168.222.140

CPU虛擬化功能

部署前請確保你的CPU虛擬化功能已開啟，分為兩種情況：

（1）虛擬機要關機設置CPU虛擬化

（2）物理機要在BIOS里開啟CPU虛擬化

虛擬機設置（內存：8G 磁盤：80G（自定義可以大一點） 虛擬化功能：開啟）

//設置虛擬機內存，添加一塊80G的硬盤

開啟虛擬化

新建分區，將硬盤所有大小都給這個分區

[root@localhost ~]# lsblk  //查看一下分區
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0   10G  0 disk 
├─sda1            8:1    0    1G  0 part /boot
└─sda2            8:2    0    9G  0 part 
  ├─centos-root 253:0    0    8G  0 lvm  /
  └─centos-swap 253:1    0    1G  0 lvm  [SWAP]
sdb               8:16   0   80G  0 disk 
sr0              11:0    1  4.2G  0 rom  
[root@localhost ~]# parted /dev/sdb
GNU Parted 3.1
使用 /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted)       //Tab兩下查看                                                           
align-check  help         mktable      quit         select       unit         
disk_set     mklabel      name         rescue       set          version      
disk_toggle  mkpart       print        rm           toggle       
(parted) mklabel 
新的磁盤標簽類型？     //Tab兩下查看                                                     
aix    amiga  bsd    dvh    gpt    loop   mac    msdos  pc98   sun    
新的磁盤標簽類型？ msdos 
(parted)      //Tab兩下查看                                                              
align-check  help         mktable      quit         select       unit         
disk_set     mklabel      name         rescue       set          version      
disk_toggle  mkpart       print        rm           toggle       
(parted) unit 
Unit?  [compact]?        //Tab兩下查看                                                   
%        chs      cyl      GiB      kiB      MiB      TB       
B        compact  GB       kB       MB       s        TiB      
Unit?  [compact]? MiB 
(parted) p                                                                
Model: VMware, VMware Virtual S (scsi)
Disk /dev/sdb: 81920MiB    //創建磁盤的大小
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Number  Start  End  Size  Type  File system  標志

(parted)           //Tab兩下查看                                                         
align-check  help         mktable      quit         select       unit         
disk_set     mklabel      name         rescue       set          version      
disk_toggle  mkpart       print        rm           toggle       
(parted) mkpart 
分區類型？  primary/主分區/extended/擴展分區? primary                     
文件系統類型？  [ext2]?         //Tab兩下查看                                            
affs0            amufs            apfs2            hfs              linux-swap(v0)
affs1            amufs0           asfs             hfs+             linux-swap(v1)
affs2            amufs1           btrfs            hfsx             nilfs2
affs3            amufs2           ext2             hp-ufs           ntfs
affs4            amufs3           ext3             jfs              reiserfs
affs5            amufs4           ext4             linux-swap       sun-ufs
affs6            amufs5           fat16            linux-swap(new)  swsusp
affs7            apfs1            fat32            linux-swap(old)  xfs
文件系統類型？  [ext2]? xfs 
起始點？ 10MiB                                                            
結束點？ 81910MiB          //比剛剛創建的小10MiB就可以了                                           
(parted) p                                                                
Model: VMware, VMware Virtual S (scsi)
Disk /dev/sdb: 81920MiB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Number  Start    End       Size      Type     File system  標志
 1      10.0MiB  81910MiB  81900MiB  primary

(parted) q                                                                
信息: You may need to update /etc/fstab.

[root@localhost ~]# udevadm settle

格式化

[root@localhost ~]# lsblk 
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0   10G  0 disk 
├─sda1            8:1    0    1G  0 part /boot
└─sda2            8:2    0    9G  0 part 
  ├─centos-root 253:0    0    8G  0 lvm  /
  └─centos-swap 253:1    0    1G  0 lvm  [SWAP]
sdb               8:16   0   80G  0 disk 
└─sdb1            8:17   0   80G  0 part 
sr0              11:0    1  4.2G  0 rom  
[root@localhost ~]# mkfs.xfs /dev/sdb1
meta-data=/dev/sdb1              isize=512    agcount=4, agsize=5241600 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0, sparse=0
data     =                       bsize=4096   blocks=20966400, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal log           bsize=4096   blocks=10237, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
[root@localhost ~]# blkid /dev/sdb1
/dev/sdb1: UUID="09888ad8-a1ef-42fb-9c36-937e071bf897" TYPE="xfs" 

創建掛載點,并進行永久掛載

[root@localhost ~]# yum -y install vim
[root@localhost ~]# mkdir /kvmdata
[root@localhost ~]# vim /etc/fstab 
UUID="09888ad8-a1ef-42fb-9c36-937e071bf897"  /kvmdata   xfs  defaults 0 0  //添加這一行
[root@localhost ~]# mount -a
[root@localhost ~]# df -Th
文件系統                類型      容量  已用  可用 已用% 掛載點
/dev/mapper/centos-root xfs       8.0G  1.2G  6.9G   15% /
devtmpfs                devtmpfs  3.9G     0  3.9G    0% /dev
tmpfs                   tmpfs     3.9G     0  3.9G    0% /dev/shm
tmpfs                   tmpfs     3.9G  8.7M  3.9G    1% /run
tmpfs                   tmpfs     3.9G     0  3.9G    0% /sys/fs/cgroup
/dev/sda1               xfs      1014M  143M  872M   15% /boot
tmpfs                   tmpfs     781M     0  781M    0% /run/user/0
/dev/sdb1               xfs        80G   33M   80G    1% /kvmdata

KVM安裝
關閉防火墻和selinux

[root@localhost ~]# systemctl stop firewalld
[root@localhost ~]# vim /etc/selinux/config 
SELINUX=disabled
[root@localhost ~]# setenforce 0
[root@localhost ~]# systemctl disable --now firewalld
Removed symlink /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
[root@localhost ~]# reboot 

部署yum源
可以配置阿里云的網絡源
阿里云官網

[root@localhost ~]# cd /etc/yum.repos.d/
[root@localhost yum.repos.d]# ls
CentOS-Base.repo  CentOS-Debuginfo.repo  CentOS-Media.repo    CentOS-Vault.repo  epel-testing.repo
CentOS-CR.repo    CentOS-fasttrack.repo  CentOS-Sources.repo  epel.repo
[root@localhost yum.repos.d]# rm -rf *
[root@localhost yum.repos.d]# ls
[root@localhost yum.repos.d]# curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  2523  100  2523    0     0   9299      0 --:--:-- --:--:-- --:--:--  9309
[root@localhost yum.repos.d]# sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
[root@localhost yum.repos.d]# ls
CentOS-Base.repo

安裝所需軟件包

[root@localhost yum.repos.d]# cd
[root@localhost ~]# yum -y install epel-release  wget net-tools unzip zip gcc gcc-c++

驗證cpu是否支持kvm，vmx是intel的 svm是AMD的

[root@localhost ~]# egrep -o 'vmx|svm' /proc/cpuinfo
vmx

安裝kvm

[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

配置網絡，因為虛擬機中的網絡，我們一般是都和公司服務器處在同一網段的，所以我們需要把kvm的網卡配置成橋接模式

[root@localhost ~]# cd /etc/sysconfig/network-scripts/
[root@localhost network-scripts]# ls
ifcfg-ens33  ifdown-ipv6    ifdown-TeamPort  ifup-ippp   ifup-routes       network-functions
ifcfg-lo     ifdown-isdn    ifdown-tunnel    ifup-ipv6   ifup-sit          network-functions-ipv6
ifdown       ifdown-post    ifup             ifup-isdn   ifup-Team
ifdown-bnep  ifdown-ppp     ifup-aliases     ifup-plip   ifup-TeamPort
ifdown-eth   ifdown-routes  ifup-bnep        ifup-plusb  ifup-tunnel
ifdown-ib    ifdown-sit     ifup-eth         ifup-post   ifup-wireless
ifdown-ippp  ifdown-Team    ifup-ib          ifup-ppp    init.ipv6-global
[root@localhost network-scripts]# cp ifcfg-ens33 ifcfg-br0
[root@localhost network-scripts]# vim ifcfg-br0 
[root@localhost network-scripts]# cat ifcfg-br0 
TYPE=bridge
BOOTPROTO=none
NAME=br0
DEVICE=br0
ONBOOT=yes
IPADDR=192.168.222.140
PREFIX=24
GATEWAY=192.168.222.2
DNS1=192.168.222.2
[root@localhost network-scripts]# vim ifcfg-ens33 
[root@localhost network-scripts]# cat ifcfg-ens33 
TYPE=Ethernet
BOOTPROTO=none
NAME=ens33
DEVICE=ens33
ONBOOT=yes
BRIDGE=br0
[root@localhost network-scripts]# systemctl restart NetworkManager
[root@localhost network-scripts]# ifdown ens33;ifup ens33
成功斷開設備 'ens33'。
連接已成功激活（D-Bus 活動路徑：/org/freedesktop/NetworkManager/ActiveConnection/3）
[root@localhost network-scripts]# cd
[root@localhost ~]# ifconfig 
br0: flags=4163  mtu 1500
        inet 192.168.222.140  netmask 255.255.255.0  broadcast 192.168.222.255
        inet6 fe80:5bffba71  prefixlen 64  scopeid 0x20
        ether 0029f0:0d  txqueuelen 1000  (Ethernet)
        RX packets 494  bytes 34964 (34.1 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 813  bytes 143186 (139.8 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ens33: flags=4163  mtu 1500
        ether 0029f0:0d  txqueuelen 1000  (Ethernet)
        RX packets 201496  bytes 194698973 (185.6 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 108153  bytes 10993998 (10.4 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10
        loop  txqueuelen 1  (Local Loopback)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

重啟libvirtd服務，并設置開機自啟

[root@localhost ~]# systemctl enable --now libvirtd
[root@localhost ~]# systemctl status libvirtd
● libvirtd.service - Virtualization daemon
   Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled; vendor preset: enabled)
   Active: active (running) since 三 2022-10-05 02:57:06 CST; 10s ago
     Docs: man:libvirtd(8)
           https://libvirt.org
 Main PID: 106910 (libvirtd)
    Tasks: 19 (limit: 32768)
   CGroup: /system.slice/libvirtd.service
           ├─106910 /usr/sbin/libvirtd
           ├─107058 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefil...
           └─107060 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --leasefil...

10月 05 02:57:07 localhost.example.com dnsmasq[107052]: listening on virbr0(#4): 192.168.122.1
10月 05 02:57:07 localhost.example.com dnsmasq[107058]: started, version 2.76 cachesize 150
10月 05 02:57:07 localhost.example.com dnsmasq[107058]: compile time options: IPv6 GNU-getopt D...fy
10月 05 02:57:07 localhost.example.com dnsmasq-dhcp[107058]: DHCP, IP range 192.168.122.2 -- 192...h
10月 05 02:57:07 localhost.example.com dnsmasq-dhcp[107058]: DHCP, sockets bound exclusively to ...0
10月 05 02:57:07 localhost.example.com dnsmasq[107058]: reading /etc/resolv.conf
10月 05 02:57:07 localhost.example.com dnsmasq[107058]: using nameserver 192.168.222.2#53
10月 05 02:57:07 localhost.example.com dnsmasq[107058]: read /etc/hosts - 2 addresses
10月 05 02:57:07 localhost.example.com dnsmasq[107058]: read /var/lib/libvirt/dnsmasq/default.a...es
10月 05 02:57:07 localhost.example.com dnsmasq-dhcp[107058]: read /var/lib/libvirt/dnsmasq/defau...e
Hint: Some lines were ellipsized, use -l to show in full.

查看kvm模塊是否加載

[root@localhost ~]# lsmod |grep kvm
kvm_intel             170086  0 
kvm                   566340  1 kvm_intel
irqbypass              13503  1 kvm

驗證安裝結果

[root@localhost ~]# virsh -c qemu:///system list
 Id    名稱                         狀態
----------------------------------------------------

[root@localhost ~]# virsh --version
4.5.0
[root@localhost ~]# virt-install --version
1.5.0

將qemu-kvm這個命令做一個軟鏈接到/usr/bin/qemu-kvm

[root@localhost ~]# ln -s /usr/libexec/qemu-kvm /usr/bin/qemu-kvm
[root@localhost ~]# ll /usr/bin/qemu-kvm
lrwxrwxrwx 1 root root 21 10月  5 03:01 /usr/bin/qemu-kvm -> /usr/libexec/qemu-kvm

查看網橋信息

[root@localhost ~]# brctl show
bridge name     bridge id               STP enabled     interfaces
br0             8000.000c295af00d       no              ens33
virbr0          8000.525400e562ac       yes             virbr0-nic

KVM管理界面安裝

Kvm的web界面是由webvirtmgr程序提供的
安裝依賴包

[root@localhost ~]# yum -y install git python-pip libvirt-python libxml2-python python-websockify supervisor nginx python-devel
.....
已安裝:
  git.x86_64 0:1.8.3.1-23.el7_8                    nginx.x86_64 1:1.20.1-9.el7                       
  python-devel.x86_64 0:2.7.5-92.el7_9             python-websockify.noarch 0:0.6.0-2.el7            
  python2-pip.noarch 0:8.1.2-14.el7                supervisor.noarch 0:3.4.0-1.el7                   

作為依賴被安裝:
  centos-indexhtml.noarch 0:7-9.el7.centos           nginx-filesystem.noarch 1:1.20.1-9.el7          
  openssl11-libs.x86_64 1:1.1.1k-4.el7               perl-Error.noarch 1:0.17020-2.el7               
  perl-Git.noarch 0:1.8.3.1-23.el7_8                 perl-TermReadKey.x86_64 0:2.30-20.el7           
  python-meld3.x86_64 0:0.6.10-1.el7                 python-rpm-macros.noarch 0:3-34.el7             
  python-setuptools.noarch 0:0.9.8-7.el7             python-srpm-macros.noarch 0:3-34.el7            
  python2-rpm-macros.noarch 0:3-34.el7               rsync.x86_64 0:3.1.2-11.el7_9                   

作為依賴被升級:
  python.x86_64 0:2.7.5-92.el7_9                 python-libs.x86_64 0:2.7.5-92.el7_9                

完畢！

可以提前做一個映射，防止訪問不了github

[root@localhost ~]# vim /etc/hosts
[root@localhost ~]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
20.205.243.166 github.com    //添加

從github上下載webvirtmgr代碼

[root@localhost ~]# cd /usr/local/src/
[root@localhost src]# git clone http://github.com/retspen/webvirtmgr.git
正克隆到 'webvirtmgr'...
remote: Enumerating objects: 5614, done.
remote: Total 5614 (delta 0), reused 0 (delta 0), pack-reused 5614
接收對象中: 100% (5614/5614), 2.97 MiB | 689.00 KiB/s, done.
處理 delta 中: 100% (3606/3606), done.

安裝webvirtmgr

[root@localhost src]# ls
webvirtmgr
[root@localhost src]# cd webvirtmgr/
[root@localhost 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)
    100% |████████████████████████████████| 8.1MB 42kB/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 104kB/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
You are using pip version 8.1.2, however version 22.2.2 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.

檢查sqlite3是否安裝

[root@localhost ~]# python
Python 2.7.5 (default, Jun 28 2022, 15:30:04) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-44)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sqlite3
>>> exit()

初始化賬號信息

[root@localhost ~]# cd /usr/local/src/webvirtmgr/
[root@localhost webvirtmgr]# python manage.py syncdb
WARNINGNo 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 //是否創建超級管理員賬號
Username (leave blank to use 'root'):   //指定超級管理員賬號用戶名，默認留空為root
Email address: lnh136@78.com   //設置超級管理員郵箱
Password:    //設置超級管理員密碼
Password (again):    //再次輸入確認超級管理員密碼
Superuser created successfully.
Installing custom SQL ...
Installing indexes ...
Installed 6 object(s) from 1 fixture(s)

拷貝web網頁到指定目錄

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/

生成一對公鑰與私鑰，由于這里webvirtmgr和kvm服務部署在同一臺主機中，所以這里本地信任。如果kvm部署在其他機器上的時候，那么就需要把公鑰發送到kvm主機中

[root@localhost webvirtmgr]# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):  //直接回車
Created directory '/root/.ssh'.
Enter passphrase (empty for no passphrase):   /直接回車
Enter same passphrase again:  /直接回車
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:GM4Wtczgi6KVA8VnhunqFApm06RP221yf9hwbhE63Ig root@localhost.example.com
The key's randomart image is:
+---[RSA 2048]----+
| ..o  . .        |
| .+.+. = .       |
|..++  + +        |
|.B.+ + =   .     |
|=.X + B S + .    |
|o+ = + E * +     |
|+     + . B .    |
| .       o =     |
|          o      |
+----[SHA256]-----+
[root@localhost webvirtmgr]# ssh-copy-id -i ~/.ssh/id_rsa.pub root@192.168.222.140
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.222.140 (192.168.222.140)' can't be established.
ECDSA key fingerprint is SHA256:FkmNy5vPRVhOZGwZpvDsgPmo4WjilEinC9gpRbRiZQQ.
ECDSA key fingerprint is MD5:570017:10:5d:1cac:197b:6662.
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@192.168.222.140's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'root@192.168.222.140'"
and check to make sure that only the key(s) you wanted were added.

配置端口轉發
可以使用ss -antl查看端口情況

[root@localhost webvirtmgr]# ssh 192.168.222.140 -L localhostlocalhost:8000 -L localhostlocalhost:60
Last login: Wed Oct  5 17:08:52 2022 from 192.168.222.1
[root@localhost ~]# ss -antl
State      Recv-Q Send-Q        Local Address:Port                       Peer Address:Port              
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                      :::22                                   :::*                  
LISTEN     0      100                     ::1:25                                   :::*                  
LISTEN     0      128                     ::1:6080                                 :::*                  
LISTEN     0      128                     ::1:8000                                 :::*                  

配置nginx

[root@localhost ~]# cp /etc/nginx/nginx.conf /etc/nginx/nginx.conf.bak
[root@localhost ~]# vim /etc/nginx/nginx.conf
//在server參數中進行修改
刪除listen       [::]:80;行
參數server_name行改成server_name  localhost;
刪除root         /usr/share/nginx/html;行
在include /etc/nginx/default.d/*.conf;行下添加
location / {
       root    html;
       index   index.html index.htm;
     }

配置nginx虛擬主機

[root@localhost ~]# vim /etc/nginx/conf.d/webvirtmgr.conf
[root@localhost ~]# cat /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;
    }
}

確保bind綁定本機的8000端口

[root@localhost ~]# vim /var/www/webvirtmgr/conf/gunicorn.conf.py
bind = '127.0.0.1:8000'   //默認
backlog = 2048            //默認
[root@localhost ~]# grep bind /var/www/webvirtmgr/conf/gunicorn.conf.py
# bind - The socket to bind.
bind = '127.0.0.1:8000'
//確保此處綁定的是本機的8000端口，這個在nginx配置中定義了，被代理的端口

重啟nginx服務設置開機自啟，查看端口是否開啟

[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      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                      :::22                                   :::*                  
LISTEN     0      100                     ::1:25                                   :::*                  
LISTEN     0      128                     ::1:6080                                 :::*                  
LISTEN     0      128                     ::1:8000                                 :::*                  

設置supervisor

[root@localhost ~]# vim /etc/supervisord.conf
//在文件最后添加如下信息
#這里command是一行
[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

啟動supervisor并設置開機自啟

[root@localhost ~]# systemctl enable --now supervisord.service
Created symlink from /etc/systemd/system/multi-user.target.wants/supervisord.service to /usr/lib/systemd/system/supervisord.service.

配置nginx用戶

[root@localhost ~]# su - nginx -s /bin/bash
-bash-4.2$ ssh-keygen
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:U+al0qUqjCY2+jySrqJYJ/+mc9fkaVtgPovqsa9+qCE nginx@localhost.example.com
The key's randomart image is:
+---[RSA 2048]----+
|                 |
|                 |
|          o o    |
|         = =     |
|        S B      |
|     o   *..     |
| .E = +..+o..    |
|==.O..++o.=+     |
|X+o.+XB*o.o.     |
+----[SHA256]-----+
-bash-4.2$ touch ~/.ssh/config
-bash-4.2$ echo -e "StrictHostKeyChecking=no
UserKnownHostsFile=/dev/null" >> ~/.ssh/config 
-bash-4.2$ chmod 0600 ~/.ssh/config
-bash-4.2$ ssh-copy-id -i ~/.ssh/id_rsa.pub root@192.168.222.140
/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 '192.168.222.140' (ECDSA) to the list of known hosts.
root@192.168.222.140's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'root@192.168.222.140'"
and check to make sure that only the key(s) you wanted were added.

-bash-4.2$ ssh root@192.168.222.140
Warning: Permanently added '192.168.222.140' (ECDSA) to the list of known hosts.
Last login: Wed Oct  5 17:34:44 2022 from 192.168.222.140
[root@localhost ~]# exit
logout
Connection to 192.168.222.140 closed.
-bash-4.2$ exit
logout
[root@localhost ~]# 
root@localhost ~]# vim /etc/polkit-1/localauthority/50-local.d/50-libvirt-remote-access.pkla
[root@localhost ~]# cat /etc/polkit-1/localauthority/50-local.d/50-libvirt-remote-access.pkla
bvirt 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 enable --now nginx
[root@localhost ~]# systemctl enable --now libvirtd

KVM web界面管理

修改nginx配置文件

[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

對系統參數進行設置

[root@localhost ~]# vim /etc/security/limits.conf
//在文件最末尾寫入
* soft nofile 655350
* hard nofile 655350

重啟服務，重讀文件

[root@localhost ~]# sysctl -p
[root@localhost ~]# systemctl enable --now nginx

安裝novnc，并通過novnc_server啟動一個vnc

[root@localhost ~]# yum -y install novnc
[root@localhost ~]# chmod +x /etc/rc.d/rc.local
[root@localhost ~]# vim /etc/rc.d/rc.local
//在最末尾加入如下行
nohup novnc_server 192.168.222.140:5920 &
[root@localhost ~]# . /etc/rc.d/rc.local
[root@localhost ~]# nohup: 忽略輸入并把輸出追加到"nohup.out"
這里會一直停在這里

使用瀏覽器訪問

登錄用戶是之前設置的默認root，密碼也是之前設置的

添加連接

創建虛擬機

1、新建存儲

2、上傳鏡像，使用FinalShell,xftp或者xshell，再或者其他工具，將鏡像文件上傳到服務器的/kvmdata目錄下存放

再開一個終端:
[root@localhost ~]# cd /kvmdata/
[root@localhost kvmdata]# ls
CentOS-7.4-x86_64-DVD-1708.iso

刷新一下網頁界面

添加網絡

實例管理，現在去創建一個虛擬機

報錯解決

報錯:
fatal: unable to access 'http://github.com/retspen/webvirtmgr.git/': Failed connect to github.com:443; Connection refused

fatal: unable to access 'http://github.com/retspen/webvirtmgr.git/': TCP connection reset by peer


解決:
[root@localhost src]# git config --global -l
fatal: unable to read config file '/root/.gitconfig': ?????????
[root@localhost src]# env|grep -i proxy