实验目的：
调整前
lv_root分区大小为50G
Lv_home分区大小为45G
调整后（将lv_home分区减少30G，将30G空间加到lv_root分区）
lv_root分区大小为80G
Lv_home分区大小为15G
操作前注意备份重要数据
1 查看磁盘使用情况
[root@lvm ~]# df –h |
Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_lvm-lv_root 50G 769M 46G 2% / tmpfs 1.9G 0 1.9G 0% /dev/shm /dev/sda1 485M 33M 427M 8% /boot /dev/mapper/vg_lvm-lv_home 45G 180M 43G 1% /home |
2 卸载/home
[root@lvm ~]# umount /home [root@lvm ~]# df -h |
Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_lvm-lv_root 50G 769M 46G 2% / tmpfs 1.9G 0 1.9G 0% /dev/shm /dev/sda1 485M 33M 427M 8% /boot |
注意：umount /home 如果提示无法卸载，则是有进程占用/home，使用如下命令来终止占用进程： |
[root@lvm ~]# fuser -m /home |
3 调整lv_home分区大小
[root@lvm ~]# resize2fs -p /dev/mapper/vg_lvm-lv_home 15G |
resize2fs 1.41.12 (17-May-2010) Please run 'e2fsck -f /dev/mapper/vg_lvm-lv_home' first. |
[root@lvm ~]# e2fsck -f /dev/mapper/vg_lvm-lv_home |
e2fsck 1.41.12 (17-May-2010) 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/mapper/vg_lvm-lv_home: 12/2992416 files (0.0% non-contiguous), 233858/11962368 blocks |
[root@lvm ~]# resize2fs -p /dev/mapper/vg_lvm-lv_home 15G |
resize2fs 1.41.12 (17-May-2010) Resizing the filesystem on /dev/mapper/vg_lvm-lv_home to 3932160 (4k) blocks. Begin pass 2 (max = 32769) Relocating blocks XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Begin pass 3 (max = 366) Scanning inode table XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Begin pass 4 (max = 6) Updating inode references XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX The filesystem on /dev/mapper/vg_lvm-lv_home is now 3932160 blocks long. |
注：resize2fs 为重新设定磁盘大小，只是重新指定一下大小，并不对结果有影响，需要下面lvreduce的配合
4 挂载/home查看使用情况
[root@lvm ~]# mount /dev/mapper/vg_lvm-lv_home /home [root@lvm ~]# df -h |
Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_lvm-lv_root 50G 769M 46G 2% / tmpfs 1.9G 0 1.9G 0% /dev/shm /dev/sda1 485M 33M 427M 8% /boot /dev/mapper/vg_lvm-lv_home 15G 168M 14G 2% /home |
5 设置空闲空间
使用lvreduce指令用于减少LVM逻辑卷占用的空间大小。可能会删除逻辑卷上已有的数据，所以在操作前必须进行确认。记得输入 “y
[root@lvm ~]# lvreduce -L 15G /dev/mapper/vg_lvm-lv_home |
WARNING: Reducing active and open logical volume to 15.00 GiB THIS MAY DESTROY YOUR DATA (filesystem etc.) Do you really want to reduce lv_home? [y/n]: y Reducing logical volume lv_home to 15.00 GiB Logical volume lv_home successfully resized |
注：lvreduce -L 15G的意思为设置当前文件系统为15G，如果lvreduce –l 15G是指从当前文件系统上减少15G
使用lvreduce减小逻辑卷的大小。注意：减小后的大小不能小于文件的大小，否则会丢失数据。
可以使用vgdisplay命令等查看一下可以操作的大小。也可以是用fdisk -l命令查看详细信息。
[root@lvm ~]# vgdisplay |
--- Volume group --- VG Name vg_lvm System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 5 VG Access read/write VG Status resizable MAX LV 0 Cur LV 3 Open LV 3 Max PV 0 Cur PV 1 Act PV 1 VG Size 99.51 GiB PE Size 4.00 MiB Total PE 25474 Alloc PE / Size 17632 / 68.88 GiB Free PE / Size 7842 / 30.63 GiB VG UUID NOS2vP-0HRm-eh9K-cHx1-ZnOS-45CA-SOvjGz |
注：vgdisplay为显示LVM卷组的元数据信息
6 把闲置空间添加到lv_root
[root@lvm ~]# df -h |
Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_lvm-lv_root 50G 769M 46G 2% / tmpfs 1.9G 0 1.9G 0% /dev/shm /dev/sda1 485M 33M 427M 8% /boot /dev/mapper/vg_lvm-lv_home 15G 168M 14G 2% /home |
[root@lvm ~]# lvextend -L +30G /dev/mapper/vg_lvm-lv_root |
Extending logical volume lv_root to 80.00 GiB Logical volume lv_root successfully resized |
注：lvextend -L +30G为在文件系统上增加30G |
[root@lvm ~]# resize2fs -p /dev/mapper/vg_lvm-lv_root |
执行后需要等待几分钟才能显示执行结果 resize2fs 1.41.12 (17-May-2010) Filesystem at /dev/mapper/vg_lvm-lv_root is mounted on /; on-line resizing required old desc_blocks = 4, new_desc_blocks = 5 Performing an on-line resize of /dev/mapper/vg_lvm-lv_root to 20971520 (4k) blocks. The filesystem on /dev/mapper/vg_lvm-lv_root is now 20971520 blocks long. |
7 查看调整结果
[root@lvm ~]# df -h |
Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_lvm-lv_root 79G 773M 74G 2% / tmpfs 1.9G 0 1.9G 0% /dev/shm /dev/sda1 485M 33M 427M 8% /boot /dev/mapper/vg_lvm-lv_home 15G 168M 14G 2% /home |
