背景：
由于在KVM虚机上做glusterfs测试，发现KVM虚拟存储空间不够。
思路：创建一个kvm img 文件指定大小200G，然后通过Virtual Machine Manager导入到对应的虚拟机
步骤：
这里以虚拟机vm2为例
创建kvm img
[root@agent-cloudstack34 2]cd /d1/virtual_machine/vm/2 #进入虚机文件目录
[root@agent-cloudstack34 2]# qemu-img create vm2-1.img 200G
Formatting ‘vm2-1.img‘, fmt=raw size=214748364800 #创建成功
[root@agent-cloudstack34 2]# ls
vm2-1.img vm2.img
使用VMM导入文件
首先关闭vm2
单击finish 完成磁盘添加
IDE Disk2 就是新增的磁盘
启动vm2
新增磁盘格式化 分区
[root@localhost ~]# fdisk -l #查看系统磁盘
Disk /dev/sdb: 214.7 GB, 214748364800 bytes ---新增磁盘
255 heads, 63 sectors/track, 26108 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
....
[root@localhost ~]# fdisk /dev/sdb #对新增磁盘分区
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0xc6997a54.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won‘t be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
WARNING: DOS-compatible mode is deprecated. It‘s strongly recommended to
switch off the mode (command ‘c‘) and change display units to
sectors (command ‘u‘).
Command (m for help): p #打印当前磁盘信息
Disk /dev/sdb: 214.7 GB, 214748364800 bytes
255 heads, 63 sectors/track, 26108 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: 0xc6997a54
Device Boot Start End Blocks Id System
Command (m for help): n #增加分区
Command action
e extended
p primary partition (1-4)
p #通常选择主分区，所以这里打一个p
Partition number (1-4): 1 #因为是第一个分却，所以只选择1
First cylinder (1-26108, default 1): 26100G #填写分区大小 200G
Last cylinder, +cylinders or +size{K,M,G} (26100-26108, default 26108):
Using default value 26108
Command (m for help): w #将分区写入硬盘
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
格式化分区
[root@localhost ~]# mkfs.ext4 /dev/sdb
mke2fs 1.41.12 (17-May-2010)
/dev/sdb is entire device, not just one partition!
Proceed anyway? (y,n) y
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
13107200 inodes, 52428800 blocks
2621440 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
1600 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, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872
Writing inode tables: done
Creating journal (32768 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.
创建目录 挂载分区
mkdir /d1
[root@localhost ~]# mount /dev/sdb /d1
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg_livedvd-lv_root
20G 5.2G 15G 27% /
tmpfs 3.9G 0 3.9G 0% /dev/shm
/dev/sda1 485M 37M 423M 8% /boot
/dev/sdb 197G 188M 187G 1% /d1
完毕
补充：
开机自动挂载/dev/sdb
/etc/fstab 新增以下内容：
/dev/sdb /d1 ext4 defaults 1 1
重启系统
原文地址：http://961911.blog.51cto.com/951911/1431284
