這裡所說的磁盤分區指的是非系統分區、非LVM分區，下面將進行縮容和擴容
當前分區結構：
[root@vm3 ~]# fdisk -l
Disk /dev/sda: 10.7 GB, 10737418240 bytes
255 heads, 63 sectors/track, 1305 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sda1 * 1 1239 9952236 83 Linux
/dev/sda2 1240 1304 522112+ 82 Linux swap / Solaris
Disk /dev/sdb: 10.7 GB, 10737418240 bytes
255 heads, 63 sectors/track, 1305 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sdb1 1 1305 10482381 83 Linux
文件系統使用率
[root@vm3 ~]# df
文件系統 1K-塊 已用可用已用%掛載點
/dev/sda1 9640260 5056192 408646056%/
tmpfs 383616 03836160%/dev/shm
/dev/sdb1 10317828 2182424792576022%/data
一、縮容
現在想縮小sdb1的容量，看到sdb1的可用空間為7925760K，我們分2G出來
1、卸載已經掛載的分區
[root@vm3 ~]# umount /data
umount: /data: device is busy
umount: /data: device is busy
[root@vm3 ~]# fuser -vm /data
USER PID ACCESS COMMAND
/data: mysql 5522 F.c.. mysqld
[root@vm3 ~]# kill 5522
[root@vm3 ~]# umount /data
2、作文件系統檢測
[root@vm3 ~]# e2fsck -f /dev/sdb1
e2fsck 1.39 (29-May-2006)
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: 197/1310720 files (22.3% non-contiguous), 586743/2620595 blocks
3、調整文件系統大小
[root@vm3 ~]# resize2fs /dev/sdb1 8317828k
resize2fs 1.39 (29-May-2006)
Resizing the filesystem on /dev/sdb1 to 2079457 (4k) blocks.
The filesystem on /dev/sdb1 is now 2079457 blocks long.
這裡設置的大小是在原來總大小的基礎上減掉了2000k，即10317828-2000000=8317828
4、調整分區大小
如何確定分區的大小呢？看上面紅色的字，說明已經重設文件系統大小為2079457 (4k) blocks,即2079457*4k=8317828k
[root@vm3 ~]# fdisk /dev/sdb <<EOF
> d
> n
> p
> 1
>
> +8317828K
> w
> EOF
注意，這裡是大寫K，1k=1000bytes,1K=1024bytes
5、再運行文件系統檢測
[root@vm3 ~]# e2fsck -f /dev/sdb1
e2fsck 1.39 (29-May-2006)
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: 197/1048576 files (22.3% non-contiguous), 578519/2079457 blocks
ok，沒問題，文件系統檢測通過。如果前面用小寫k，就會出錯，如下：
[root@vm3 ~]# e2fsck -f /dev/sdb1
e2fsck 1.39 (29-May-2006)
The filesystem size (according to the superblock) is 2079457 blocks
The physical size of the device is 2032214 blocks
Either the superblock or the partition table is likely to be corrupt!
Abort<y>? yes
意思是說分區大小小於文件系統大小
6、掛載分區
[root@vm3 ~]# mount /dev/sdb1 /data
[root@vm3 ~]# ls /data
db1 db2 log lost+found mongodb mysql
ok，數據還在，調整成功！
7、為剩余空間創建分區
[root@vm3 ~]# fdisk /dev/sdb <<EOF
> n
> p
> 2
>
>
> w
> EOF
8、格式化分區、掛載
[root@vm3 ~]# mkfs.ext3 /dev/sdb2
[root@vm3 ~]# mount /dev/sdb2 /mnt
[root@vm3 ~]# ls /mnt
lost+found
9、看文件系統使用率
[root@vm3 ~]# df
文件系統 1K-塊已用可用已用%掛載點
/dev/sda1 96402605055024408762856%/
tmpfs 38361603836160%/dev/shm
/dev/sdb1 8186172 2182420 600375227%/data
/dev/sdb2 21188646877619424564%/mnt
