需求，给你的kvm机器增加500g的neicun

1.vmware增家50g的硬盘

2.重启vm虚拟机

mkfs.xfs /dev/sdb
mkdir /new_data
mount -t xfs /dev/sdb /new_data
#将虚拟机的磁盘放到/new_data下1先给虚拟机guanji
[root@localhost ~]# virsh shutdown linux0224_cento7
Domain linux0224_cento7 is being shutdown#挪磁盘
[root@localhost ~]#  mv /data/* /new_data
#修修改虚拟机的配置，识别新磁盘的路径
[root@localhost ~]# virsh edit linux0224_cento732   </pm>33   <devices>34     <emulator>/usr/libexec/qemu-kvm</emulator>35     <disk type='file' device='disk'>36       <driver name='qemu' type='raw'/>37       <source file='/data/linux0224_cento7.raw'/>38       <target dev='vda' bus='virtio'/>39       <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
找到37行，更改一下，开机即可#虚拟机改名
[root@localhost ~]# virsh list --allId    Name                           State
-----------------------------------------------------     linux0224_cento7               shut off[root@localhost ~]# virsh domrename linux0224_cento7 
error: command 'domrename' requires <new-name> option
[root@localhost ~]# virsh domrename linux0224_cento7  centos7
Domain successfully renamed[root@localhost ~]# virsh listId    Name                           State
----------------------------------------------------[root@localhost ~]# virsh list --allId    Name                           State
-----------------------------------------------------     centos7                        shut off#磁盘格式转换
/data/linux0224_cento7.raw raw缺点
占空间
不支持快照
qcow2
省空间
支持快照virsh命令是管理虚拟机的
qemu-img是管理底层虚拟化设备的，如查看信心[root@localhost ~]# qemu-img info /data/linux0224_cento7.raw 
image: /data/linux0224_cento7.raw
file format: raw
virtual size: 5.0G (5368709120 bytes)
disk size: 1.6G
#更改文件类型   给他3g的存储空间
[root@localhost ~]#  qemu-img create -f qcow2 /data/linux0224_cento7.qcow2 3G
Formatting '/data/linux0224_cento7.qcow2', fmt=qcow2 size=3221225472 encryption=off cluster_size=65536 lazy_refcounts=off给3G感觉太少了，多给4G，只能增加不能减少
[root@localhost ~]# qemu-img resize /data/linux0224_cento7.qcow2  +4G
Image resized.#镜像转换，将raw镜像换成 qcow 格式，需要先关机 
-f指定源格式 -O指定输出格式
convert，转换
[root@localhost ~]# qemu-img convert -f raw -O qcow2 /data/linux0224_cento7.raw /data/linux0224_cento7.qcow2 
修改磁盘的配置文件，读取新的磁盘格式virsh edit centos735     <disk type='file' device='disk'>36       <driver name='qemu' type='qcow2'/>37       <source file='/data/linux0224_cento7.qcow2'/>#访问测试
[root@localhost ~]# virsh domifaddr centos7Name       MAC address          Protocol     Address
-------------------------------------------------------------------------------vnet0      52:54:00:f2:60:4e    ipv4         192.168.122.218/24[root@localhost ~]# ssh root@192.168.122.218root@192.168.122.218's password: Last login: Sun Jun  2 12:07:42 2024
[root@localhost ~]# 
[root@localhost ~]# hostname -I
192.168.122.218 

3.添加虚拟磁盘

1，进入磁盘目录创建一个新的硬盘
-f qcow2 更省空间，支持快照
[root@localhost ~]# qemu-img create -f qcow2 /data/centos7 5G
Formatting '/data/centos7', fmt=qcow2 size=5368709120 encryption=off cluster_size=65536 lazy_refcounts=off #额外在添加一块盘，无需在关机
attch 附属
--live 激活他
--cache=none 要不要无所谓，不要缓存
vdb  磁盘名字
attach-disk 临时热添加磁盘
[root@localhost ~]# virsh attach-disk centos7 /data/centos7 vdb --live --cache=none --subdriver=qcow2
Disk attached successfully删除磁盘
[root@localhost ~]# virsh detach-disk centos7 vdb
Disk detached successfully永久化添加kvm磁盘
[root@localhost ~]# qemu-img create -f qcow2 /data/centos7 5G
[root@localhost ~]# virsh attach-disk centos7 /data/centos7 vdb --live --cache=none --subdriver=qcow2
[root@localhost data]# virsh dumpxml centos7 > /opt/lastest_centos7.xml
[root@localhost data]# virsh define /opt/lastest_centos7.xml 
Domain centos7 defined from /opt/lastest_centos7.xml在关机重启测试一下

创建快照

创建虚拟机快照 
--name init-ok就是给这快照起一个名字
[root@localhost data]# virsh snapshot-create-as --name init-ok centos7
Domain snapshot init-ok created#查看有哪些快照
[root@localhost data]# virsh snapshot-list centos7Name                 Creation Time             State
------------------------------------------------------------init-ok              2024-06-05 20:49:03 +0800 running恢复快照
--snapshotname init-ok 指定恢复快照的名称
[root@localhost data]# virsh snapshot-revert centos7 --snapshotname init-ok免密登录到虚拟机
[root@localhost data]# ssh-keygen -t rsa
[root@localhost data]# ssh-copy-id root@ip删除快照
[root@localhost data]# virsh snapshot-delete centos7 --snapshotname init-ok
Domain snapshot init-ok deleted[root@localhost data]# virsh snapshot-list centos7Name                 Creation Time             State
------------------------------------------------------------

kvm克隆

克隆时必须关机[root@localhost data]# virsh shutdown centos7
Domain centos7 is being shutdown--auto-clone从原始客户机配置自动生成克隆名称以及存储路径
-o指定原有的虚拟机
-n指定新的虚拟机的名字[root@localhost data]# virt-clone --auto-clone -o centos7 -n new_centos7
Allocating 'linux0224_cento7-clone.qcow2'                                                                                                                               | 5.0 GB  00:00:03     
Allocating 'new_centos7'                                                                                                                                                | 5.0 GB  00:00:00     Clone 'new_centos7' created successfully.[root@localhost data]# virsh list --allId    Name                           State
-----------------------------------------------------     centos7                        shut off-     new_centos7                    shut off修改端口
[root@localhost data]# virsh vncdisplay centos7
:0virsh edit centos7105     <graphics type='vnc' port='-1' autoport='yes' listen='0.0.0.0'>   把autoport改为no  port改称你想要端口 比如port='5'106       <listen type='address' address='0.0.0.0'/>107     </graphics>[root@localhost data]# virsh define /etc/libvirt/qemu/new_centos7.xml在关机重启即可
virsh shutdown centos7
virsh start centos7

添加虚拟网桥

此时在kvm虚拟机里面跑了一个nginx服务，想在宿主机访问，显示没有路由
[root@test3 ~]# virsh domifaddr centos7Name       MAC address          Protocol     Address
-------------------------------------------------------------------------------vnet0      52:54:00:24:be:9e    ipv4         192.168.122.232/24[root@test3 ~]# curl 192.168.122.232
curl: (7) Failed connect to 192.168.122.232:80; No route to host#创建一个虚拟网桥，和ens33做一个桥接
[root@test3 ~]# virsh iface-bridge  ens33 kvm-bridge0 
Created bridge kvm-bridge0 with attached device ens33