Linux LVM扩容和缩容

将原硬盘上的LVM分区/dev/mapper/RHEL-Data由原来的60G扩展到80G

Step1:将LVData扩容+20G，如下图：

[root@esc data]# lvextend -L +20G /dev/RHEL/Data
Size of logical volume RHEL/Data changed from 60.00 GiB (15360 extents) to 80.00 GiB (20480 extents).
Logical volume RHEL/Data successfully resized.
[root@esc data]#

Step2:检查LV，如下图：

[root@esc data]# e2fsck -f /dev/RHEL/Data
e2fsck 1.42.9 (28-Dec-2013)
/dev/RHEL/Data is mounted.
e2fsck: Cannot continue, aborting.

[root@esc data]#

Step3:重新定义分区大小，如下图：

[root@esc ~]# resize2fs /dev/RHEL/Data
resize2fs 1.42.9 (28-Dec-2013)
resize2fs: Bad magic number in super-block while trying to open /dev/RHEL/Data    //EXT4的扩容使用 resize2fs 
Couldn't find valid filesystem superblock.
[root@esc ~]#

[root@esc ~]# xfs_growfs /dev/RHEL/Data                                                               //XFS扩容使用xfs_growfs
meta-data=/dev/mapper/RHEL-Data isize=256 agcount=4, agsize=3932160 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0 finobt=0
data = bsize=4096 blocks=15728640, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal bsize=4096 blocks=7680, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 15728640 to 20971520
[root@esc ~]#

Step4:查看扩容后的分区容量，如下图：

[root@esc ~]# df -h
Filesystem Size Used Avail Use% Mounted on
devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs 2.0G 8.5M 2.0G 1% /run
tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup
/dev/mapper/centos-root 45G 3.5G 41G 8% /
/dev/sda1 497M 164M 333M 33% /boot
/dev/mapper/centos-home 22G 33M 22G 1% /home
tmpfs 393M 0 393M 0% /run/user/1000
/dev/mapper/RHEL-Data 80G 21G 60G 26% /data                 //从原来60G扩展到了80G

将原硬盘上的LVM分区/dev/mapper/RHEL-Data由原来的80G扩展到60G

e2fsck -f /dev/RHEL/Data  #检查磁盘错误 （针对ext4执行）

resize2fs /dev/RHEL/Data  60G #更新逻辑卷信息（针对ext4执行）

lvresize -L 20G /dev/RHEL/Data  #重新设定大小

注意：XFS文件系统不支持缩容。