step1：创建一个qcow2格式的磁盘镜像
[root@kvm ~]# qemu-img create -f qcow2 /kvm/centos1_1.qcow2 5G
Formatting '/kvm/centos1_1.qcow2', fmt=qcow2 size=5368709120 encryption=off cluster_size=65536
[root@kvm ~]# virsh destroy centos1
Domain centos1 destroyed
step2：编辑/etc/libvirt/qemu/centos1.xml 增加磁盘模块
[root@kvm ~]# vim /etc/libvirt/qemu/centos1.xml 或者 [root@kvm ~]# virsh edit centos1 <disk type='file' device='disk'> <driver name='qemu' type='qcow2' cache='none'/> <source file='/kvm/centos1_1.qcow2'/> <target dev='vdb' bus='virtio'/> </disk>
开启虚拟机
[root@kvm ~]# virsh start centos1 [root@kvm ~]# virsh console centos1
step3：分区
[root@localhost ~]# fdisk -l Disk /dev/vda: 16.1 GB, 16106127360 bytes 16 heads, 63 sectors/track, 31207 cylinders Units = cylinders of 1008 * 512 = 516096 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000e5856 Device Boot Start End Blocks Id System /dev/vda1 * 3 1018 512000 83 Linux Partition 1 does not end on cylinder boundary. /dev/vda2 1018 20806 9972736 8e Linux LVM Partition 2 does not end on cylinder boundary. /dev/vda3 20807 31207 5242104 83 Linux Disk /dev/vdb: 5368 MB, 5368709120 bytes 16 heads, 63 sectors/track, 10402 cylinders Units = cylinders of 1008 * 512 = 516096 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/mapper/VolGroup-lv_root: 14.5 GB, 14533263360 bytes 255 heads, 63 sectors/track, 1766 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/VolGroup-lv_swap: 1040 MB, 1040187392 bytes 255 heads, 63 sectors/track, 126 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
分区
[root@localhost ~]# fdisk /dev/vdb
Command (m for help): p
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4):
Value out of range.
Partition number (1-4): 1
First cylinder (1-10402, default 1):
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-10402, default 10402):
Using default value 10402
Command (m for help): p
Disk /dev/vdb: 5368 MB, 5368709120 bytes
16 heads, 63 sectors/track, 10402 cylinders
Units = cylinders of 1008 * 512 = 516096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x3d00f46a
Device Boot Start End Blocks Id System
/dev/vdb1 1 10402 5242576+ 83 Linux
Command (m for help): w
The partition table has been altered![root@localhost ~]# partx /dev/vdb # 1: 63- 10485215 ( 10485153 sectors, 5368 MB) # 2: 0- -1 ( 0 sectors, 0 MB) # 3: 0- -1 ( 0 sectors, 0 MB) # 4: 0- -1 ( 0 sectors, 0 MB) [root@localhost ~]# ll /dev/vdb* brw-rw----. 1 root disk 252, 16 Jan 17 01:22 /dev/vdb brw-rw----. 1 root disk 252, 17 Jan 17 01:22 /dev/vdb1
格式化
[root@localhost ~]# mkfs.ext4 /dev/vdb1 mke2fs 1.41.12 (17-May-2010) Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 327680 inodes, 1310644 blocks 65532 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=1342177280 40 block groups 32768 blocks per group, 32768 fragments per group 8192 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736 Writing inode tables: done Creating journal (32768 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 27 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override.
挂载/自动挂载
[root@localhost ~]# mkdir /data [root@localhost ~]# mount /dev/vdb1 /data/ EXT4-fs (vdb1): mounted filesystem with ordered data mode. Opts:
[root@localhost ~]# df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/VolGroup-lv_root ext4 14G 685M 12G 6% / tmpfs tmpfs 246M 0 246M 0% /dev/shm /dev/vda1 ext4 477M 33M 419M 8% /boot /dev/vdb1 ext4 4.8G 10M 4.6G 1% /data
[root@localhost ~]# vi /etc/fstab /dev/vdb1 /data ext4 defaults 0 0
