KVM中Linux虚拟机的硬盘添加方法

[root@cache01 ~]# df -hT
Filesystem           Type   Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root
                     ext4   8.3G  937M  7.0G  12% /
tmpfs                tmpfs  119M     0  119M   0% /dev/shm
/dev/vda1            ext4   477M   33M  419M   8% /boot
[root@cache01 ~]#
生成一块新的硬盘
[root@bass virhost]# qemu-img create -f raw o5cache.add.disk.raw 2G
Formatting '05cache.add.disk.raw', fmt=raw size=2147483648
 <disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='none'/>
      <source file='/home/virhost/05cache.add.disk.raw'/>
      <target dev='vda' bus='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </disk>
[root@bass virhost]# virsh start 05cache
Domain 05cache started

[root@bass virhost]# virsh attach-disk 05cache /home/virhost/05cache.add.disk.raw vdb --cache none
Disk attached successfully
virsh edit 05cache---------------->
<disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='none'/>
      <source file='/home/virhost/05cache.img'/>
      <target dev='vda' bus='virtio'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </disk>
    <disk type='block' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <target dev='hdc' bus='ide'/>
      <readonly/>
      <address type='drive' controller='0' bus='1' target='0' unit='0'/>
    </disk>
[root@cache01 ~]# fdisk -l

Disk /dev/vda: 10.7 GB, 10737418240 bytes
16 heads, 63 sectors/track, 20805 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: 0x000c1fb8

   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.

Disk /dev/vdb: 2147 MB, 2147483648 bytes #挂上的新的硬盘
16 heads, 63 sectors/track, 4161 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: 9168 MB, 9168748544 bytes
255 heads, 63 sectors/track, 1114 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

在虚拟机中对硬盘进行格式化

[root@cache01 ~]# mkfs.ext4 /dev/vdb
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
131072 inodes, 524288 blocks
26214 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=536870912
16 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
	32768, 98304, 163840, 229376, 294912

Writing inode tables: done
Creating journal (16384 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 34 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

接下来建一个目录来挂载新的硬盘：

[root@cache01 ~]# mkdir /nd
[root@cache01 ~]# mkdir /nd
[root@cache01 ~]# mount /dev/vdb /nd/
＃获取硬盘的UUID
[root@cache01 ~]# blkid /dev/vdb
/dev/vdb: UUID="a35e0890-3aa6-47a7-921c-c2cb9dd431e6" TYPE="ext4"

将挂载添加到开机启动中：

[root@cache01 ~]# cat /etc/fstab 

#
# /etc/fstab
# Created by anaconda on Tue Jun 28 08:57:38 2016
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/VolGroup-lv_root /                       ext4    defaults        1 1
UUID=04e8e77f-2604-4683-833b-a06a7300c7a3 /boot                   ext4    defaults        1 2
/dev/mapper/VolGroup-lv_swap swap                    swap    defaults        0 0
tmpfs                   /dev/shm                tmpfs   defaults        0 0
devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
sysfs                   /sys                    sysfs   defaults        0 0
proc                    /proc                   proc    defaults        0 0
UUID=a35e0890-3aa6-47a7-921c-c2cb9dd431e6 /nd  ext4     defaults        1 2

[root@cache01 ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root
                      8.3G  644M  7.3G   9% /
tmpfs                 119M     0  119M   0% /dev/shm
/dev/vda1             477M   33M  419M   8% /boot
/dev/vdb              2.0G  3.0M  1.9G   1% /nd