Linux命令行Kvm虚拟机基础操作【显哥出品，必为精品】

1.显示虚拟机列表

#显示所有虚拟机
[root@kvm /opt]# virsh list --all
 Id    Name                           State
----------------------------------------------------
 7     db01                           running
 -     centos6                        shut off

#显示正在运行的虚拟机
[root@kvm /opt]# virsh list 
 Id    Name                           State
----------------------------------------------------
 7     db01                           running

2.启动、关闭虚拟机

#启动虚拟机
[root@kvm /opt]# virsh start centos6 
Domain centos6 started

#关闭虚拟机
[root@kvm /opt]# virsh shutdown centos6 
Domain centos6 is being shutdown

#强制关闭虚拟机（相当于拔电源）
[root@kvm /opt]# virsh destroy centos6 
Domain centos6 destroyed

3.显示主机信息

[root@kvm /opt]# virsh dominfo centos6 
Id:             -
Name:           centos6
UUID:           9a58937a-e12d-4006-90aa-b9b13f1f3728
OS Type:        hvm
State:          shut off
CPU(s):         1
Max memory:     1048576 KiB
Used memory:    1048576 KiB
Persistent:     yes
Autostart:      disable
Managed save:   no
Security model: none
Security DOI:   0

4.显示主机对应的端口

[root@kvm /opt]# virsh vncdisplay db01 
:0

[root@kvm /opt]# virsh vncdisplay web01 
:1

[root@kvm /opt]# virsh vncdisplay web02 
:2

[root@kvm /opt]# netstat -lntp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
tcp        0      0 0.0.0.0:5900            0.0.0.0:*               LISTEN      15822/qemu-kvm      #db01 
tcp        0      0 0.0.0.0:5901            0.0.0.0:*               LISTEN      17311/qemu-kvm      #web01 
tcp        0      0 0.0.0.0:5902            0.0.0.0:*               LISTEN      17351/qemu-kvm      #web02 

5.调内存

#将内存进行调小 
[root@kvm01-server /opt]# virsh  setmem   web01   524288

[root@kvm01-server /opt]# virsh   dominfo   web01 
Id:             4
Name:           web01
UUID:           71348068-6685-4134-9fca-15e8c686dcfc
OS Type:        hvm
State:          running
CPU(s):         1
CPU time:       21.8s
Max memory:     1048576 KiB
Used memory:    524288 KiB
Persistent:     yes
Autostart:      disable
Managed save:   no
Security model: none
Security DOI:   0

#在关机状态下调整最大内存 
[root@kvm01-server /opt]# virsh   setmaxmem   web01   2097152

[root@kvm01-server /opt]# virsh  dominfo   web01 
Id:             -
Name:           web01
UUID:           71348068-6685-4134-9fca-15e8c686dcfc
OS Type:        hvm
State:          shut off
CPU(s):         1
Max memory:     2097152 KiB
Used memory:    1048576 KiB
Persistent:     yes
Autostart:      disable
Managed save:   no
Security model: none
Security DOI:   0

6.导入、导出配置

#导出配置
[root@kvm /opt]# virsh dumpxml web01 >web01_bak.xml

#导入配置
[root@kvm /opt]# virsh   define    web01_bak.xml 
Domain web01 defined from web01_bak.xml

7.重命名虚拟机名称

#重命名虚拟主机名   关机状态下

[root@kvm01-server /opt]# virsh  shutdown  web01 
Domain web01 is being shutdown


[root@kvm01-server /opt]# virsh  domrename   web01   lx
Domain successfully renamed

[root@kvm01-server /opt]# virsh  list --all
 Id    Name                           State
----------------------------------------------------
 -     lx                            shut off

8.开机自启动

#要想虚拟机能够开机自启动，必须你的libvirtd服务是开机启动，开机自启动就是基于一种软链接的方式 

[root@kvm01-server /opt]# virsh   dominfo   web01  | grep start
Autostart:      disable

[root@kvm01-server /opt]# systemctl  enable   libvirtd
[root@kvm01-server /opt]# virsh  autostart   web01
Domain web01 marked as autostarted

[root@kvm01-server /opt]# virsh   dominfo   web01  | grep start
Autostart:      enable
[root@kvm01-server /opt]# ll /etc/libvirt/qemu
total 8
drwxr-xr-x 2 root root   21 Jul 28 18:11 autostart
drwx------ 3 root root   42 Jul 28 16:09 networks
-rw------- 1 root root 4403 Jul 28 18:08 web01.xml
[root@kvm01-server /opt]# ll /etc/libvirt/qemu/autostart/
total 0
lrwxrwxrwx 1 root root 25 Jul 28 18:11 web01.xml -> /etc/libvirt/qemu/web01.xml

9.挂起与恢复

#挂起
[root@kvm01-server /opt]# virsh  suspend   web01
Domain web01 suspended

#恢复
[root@kvm01-server /opt]# virsh  resume    web01
Domain web01 resumed

10.虚拟机的console登录

[root@kvm01-server /opt]# ssh  root@192.168.122.158
root@192.168.122.158  password: 
Last login: Tue Jul 28 18:09:14 2020
[root@web01 ~]# grubby --update-kernel=ALL --args="console=ttyS0,115200n8"
[root@web01 ~]# reboot
Connection to 192.168.122.158 closed by remote host.
Connection to 192.168.122.158 closed.
[root@kvm01-server /opt]# 

[root@kvm01-server /opt]# virsh  console   web01
Connected to domain web01
Escape character is ^]

CentOS Linux 7 (Core)
Kernel 3.10.0-957.el7.x86_64 on an x86_64

kvm login: root
Password: 
Last login: Tue Jul 28 18:51:55 from gateway
[root@web01 ~]#