云平台客户的

步骤

1.备份

就算是无损的扩容，但难免会出什么意外，备份是必不可少的，一般云平台都有备份功能，可直接对磁盘做一次全量备份。

2.用fdisk重新分区

默认的分区如下

root@i-abnawjwo:/# df

Filesystem 1K-blocks Used Available Use% Mounted on

udev 497752 4 497748 1% /dev

tmpfs 101700 440 101260 1% /run

/dev/sda1 20509308 1337636 18106816 7% /

none 4 0 4 0% /sys/fs/cgroup

none 5120 0 5120 0% /run/lock

none 508488 0 508488 0% /run/shm

none 102400 0 102400 0% /run/user

/dev/sdc1 10190136 23032 9626432 1% /data

root@i-abnawjwo:/data# cat hello

test1

卸载当前的分区umount /dev/sdc1

若是卸载不掉，有可能是有进程再用，可以用fuser或者lsof查看

fuser -m -v /data

fuser -m -v -i -k /data

lsof /data

卸载掉后fdisk删除原来的分区，重新分区， 注意开始的磁柱号要和原来的一致(这是保证数据不丢失的关键步骤)

root@i-abnawjwo:/# umount /data

root@i-abnawjwo:/# fdisk /dev/sdc

Command (m for help): d

Selected partition 1

Command (m for help): n

Partition type:

p primary (0 primary, 0 extended, 4 free)

e extended

Select (default p):

Using default response p

Partition number (1-4, default 1):

Using default value 1

First sector (2048-104857599, default 2048):

Using default value 2048

Last sector, +sectors or +size{K,M,G} (2048-104857599, default 104857599):

Using default value 104857599

Command (m for help): p

Disk /dev/sdc: 53.7 GB, 53687091200 bytes

64 heads, 32 sectors/track, 51200 cylinders, total 104857600 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x305cddae

Device Boot Start End Blocks Id System

/dev/sdc1 2048 104857599 52427776 83 Linux

Command (m for help): wq

The partition table has been altered!

Calling ioctl() to re-read partition table.

Syncing disks.

重启系统

3.检测分区，扩展分区大小

root@i-abnawjwo:~# e2fsck -f /dev/sdb1

e2fsck 1.42.9 (4-Feb-2014)

Pass 1: Checking inodes, blocks, and sizes

Pass 2: Checking directory structure

Pass 3: Checking directory connectivity

Pass 4: Checking reference counts

Pass 5: Checking group summary information

/dev/sdb1: 12/655360 files (0.0% non-contiguous), 79664/2621440 blocks

root@i-abnawjwo:~# resize2fs -p /dev/sdb1

resize2fs 1.42.9 (4-Feb-2014)

Resizing the filesystem on /dev/sdb1 to 13106944 (4k) blocks.

The filesystem on /dev/sdb1 is now 13106944 blocks long.

4.重新挂载，查看分区大小，检查数据

root@i-abnawjwo:~# mount /dev/sdb1 /data/

root@i-abnawjwo:/data# cat hello

acasdcacsa

root@i-abnawjwo:/data# df

Filesystem 1K-blocks Used Available Use% Mounted on

udev 497752 4 497748 1% /dev

tmpfs 101700 428 101272 1% /run

/dev/sda1 20509308 1337768 18106684 7% /

none 4 0 4 0% /sys/fs/cgroup

none 5120 0 5120 0% /run/lock

none 508488 0 508488 0% /run/shm

none 102400 0 102400 0% /run/user

/dev/sdb1 51474044 33100 48803172 1% /data