逻辑卷实战案例-逻辑卷裁剪

案例需求

将lv1逻辑卷由原来的3G缩小为2G

案例思路

1、卸载逻辑卷
2、扫描逻辑卷
3、裁剪率lv1文件系统
4、裁剪逻辑卷lv1
5、挂载使用

案例实现

ext分区逻辑卷裁剪

[root@zutuanxue /]# umount /lv1
[root@zutuanxue /]# e2fsck -f /dev/vg1/lv1      检验文件系统
[root@zutuanxue /]# resize2fs /dev/vg1/lv1  2G  裁剪文件系统到2G
[root@zutuanxue /]# lvreduce /dev/vg1/lv1 -L 2G 裁剪逻辑卷
[root@zutuanxue /]# mount /dev/vg1/lv1 /lv1/        挂载使用
[root@zutuanxue /]# df -h
文件系统             容量  已用  可用 已用% 挂载点
/dev/mapper/vg1-lv1  2.0G  9.0M  1.8G    1% /lv1

xfs分区逻辑卷裁剪

案例思路：
1、将lv2的文件系统格式化为xfs
2、将/dev/vg1/lv2挂载到/lv2
3、在/lv2中建立一个文件，写入内容
4、备份数据
5、卸载分区并裁剪逻辑卷
6、格式化裁剪后的逻辑卷
7、导入数据

1)备份数据命令
xfsdump
2）备份数据
[root@zutuanxue /]# xfsdump -f /root/lv2.img /lv2
#挂载点目录后面不要加"/"
xfsdump: using file dump (drive_simple) strategy
xfsdump: version 3.1.8 (dump format 3.0) - type ^C for status and control

 ============================= dump label dialog ==============================

please enter label for this dump session (timeout in 300 sec)
 -> lv2
session label entered: "lv2"

 --------------------------------- end dialog ---------------------------------

xfsdump: level 0 dump of localhost.localdomain:/lv2
xfsdump: dump date: Tue Dec 10 06:33:44 2019
xfsdump: session id: 15936371-b967-4c2c-8995-49eb702792fe
xfsdump: session label: "lv2"
xfsdump: ino map phase 1: constructing initial dump list
xfsdump: ino map phase 2: skipping (no pruning necessary)
xfsdump: ino map phase 3: skipping (only one dump stream)
xfsdump: ino map construction complete
xfsdump: estimated dump size: 20800 bytes

 ============================= media label dialog =============================

please enter label for media in drive 0 (timeout in 300 sec)
 -> lv2
media label entered: "lv2"

 --------------------------------- end dialog ---------------------------------

xfsdump: creating dump session media file 0 (media 0, file 0)
xfsdump: dumping ino map
xfsdump: dumping directories
xfsdump: dumping non-directory files
xfsdump: ending media file
xfsdump: media file size 21016 bytes
xfsdump: dump size (non-dir files) : 0 bytes
xfsdump: dump complete: 14 seconds elapsed
xfsdump: Dump Summary:
xfsdump:   stream 0 /root/lv2.img OK (success)
xfsdump: Dump Status: SUCCESS


3)裁剪
[root@zutuanxue ~]# umount /lv2
[root@zutuanxue ~]# lvreduce /dev/vg1/lv2 -L 100M
  WARNING: Reducing active logical volume to 2.00 GiB.
  THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce vg01/lv01? [y/n]: y
  Size of logical volume vg01/lv01 changed from 7.00 GiB (1792 extents) to 2.00 GiB (512 extents).
  Logical volume vg01/lv01 successfully resized.

4）格式化
[root@zutuanxue ~]# mkfs.xfs -f /dev/vg1/lv2
[root@zutuanxue ~]# mount /dev/vg1/lv2 /lv2

5）恢复数据 -f source
[root@zutuanxue ~]# xfsrestore -f /root/lv2.img /lv2
.
.
.
xfsrestore: Restore Status: SUCCESS


root@zutuanxue ~]# df -h
文件系统             容量  已用  可用 已用% 挂载点
/dev/mapper/vg1-lv2   95M  6.0M   89M    7% /lv2



[root@zutuanxue ~]# cat /lv2/filea 
hahaha