创建一块新磁盘
[root@kvm images]# qemu-img create -f qcow2 vm1-disk.qcow2 2G
Formatting 'vm1-disk1', fmt=qcow2 size=2147483648 encryption=off cluster_size=65536
[root@kvm images]# ls
vm1-disk.qcow2 vm1.img vm1.qcow2 vm2.img
编辑配置文件
[root@kvm images]# virsh edit vm1
增加
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2' cache='none'/>
<source file='/home/kvm/images/vm1-disk.qcow2'/>
<target dev='hdb' bus='ide'/>
</disk>
然后 启动vm1 实例
[root@kvm images]# virsh start vm1
Domain vm1 started
连接虚拟机,查看磁盘
[root@vm1 ~]# fdisk -l
Disk /dev/sda: 10.7 GB, 10737418240 bytes
255 heads, 63 sectors/track, 1305 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000aaa7c
Device Boot Start End Blocks Id System
/dev/sda1 * 1 64 512000 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 64 1306 9972736 8e Linux LVM
Disk /dev/sdb: 2147 MB, 2147483648 bytes
255 heads, 63 sectors/track, 261 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/mapper/vg_vm1-lv_root: 9135 MB, 9135194112 bytes
255 heads, 63 sectors/track, 1110 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/mapper/vg_vm1-lv_swap: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
然后挂载磁盘什么的就不用多说了。