由于项目规定程序目录在根目录，在安装系统时没有及时规划分区，导致根分区空间太小，现在决定对根分区进行扩容.
准备将home目录所在的分区进行缩容，将缩容的空间扩容到根分区.
[root@service1 cloud]# df -Th Filesystem Type Size Ued Avail Use% Mounted on /dev/mapper/centos-root xfs 50G 1006M 49G 2% / devtmpfs devtmpfs 7.8G 0 7.8G 0% /dev tmpfs tmpfs 7.8G 0 7.8G 0% /dev/shm tmpfs tmpfs 7.8G 9.2M 7.8G 1% /run tmpfs tmpfs 7.8G 0 7.8G 0% /sys/fs/cgroup /dev/xvda1 xfs 1014M 145M 870M 15% /boot /dev/mapper/centos-home xfs 42G 33M 42G 1% /home tmpfs tmpfs 1.6G 0 1.6G 0% /run/user/0
#卸载磁盘home目录的挂载分区
[root@service1 cloud]# umount /dev/mapper/centos-home
#将卸载的磁盘分区重新进行格式化成ext4格式.
[root@service1 cloud]# mkfs.ext4 /dev/mapper/centos-home mke2fs 1.42.9 (28-Dec-2013) Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 2695168 inodes, 10778624 blocks 538931 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=2160066560 329 block groups 32768 blocks per group, 32768 fragments per group 8192 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 4096000, 7962624 Allocating group tables: done Writing inode tables: done Creating journal (32768 blocks): done Writing superblocks and filesystem accounting information: done
#强制检查 /dev/mapper/centos-home 是否正常，如果有异常便自动修复
[root@service1 cloud]# e2fsck -f /dev/mapper/centos-home e2fsck 1.42.9 (28-Dec-2013) 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/centos-home: 11/2695168 files (0.0% non-contiguous), 214252/10778624 block
#resize2fs扩展文件系统，将/dev/mapper/centos-home文件系统扩展为20G大小.
[root@service1 cloud]# resize2fs /dev/mapper/centos-home 20G resize2fs 1.42.9 (28-Dec-2013) Resizing the filesystem on /dev/mapper/centos-home to 5242880 (4k) blocks. The filesystem on /dev/mapper/centos-home is now 5242880 blocks long.
#挂载文件系统到home目录,我们发现为20G.
[root@service1 cloud]# mount /dev/mapper/centos-home /home/ [root@service1 cloud]# df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/centos-root xfs 50G 1006M 49G 2% / devtmpfs devtmpfs 7.8G 0 7.8G 0% /dev tmpfs tmpfs 7.8G 0 7.8G 0% /dev/shm tmpfs tmpfs 7.8G 9.2M 7.8G 1% /run tmpfs tmpfs 7.8G 0 7.8G 0% /sys/fs/cgroup /dev/xvda1 xfs 1014M 145M 870M 15% /boot tmpfs tmpfs 1.6G 0 1.6G 0% /run/user/0 /dev/mapper/centos-home ext4 20G 45M 19G 1% /home
# lvreduce缩小逻辑卷,/dev/mapper/centos-home文件系统对应的逻辑卷为/dev/mapper/centos-home，缩小逻辑区22G。
[root@service2 ~]# lvreduce -L 22G /dev/mapper/centos-home WARNING: Reducing active and open logical volume to 22.00 GiB. THIS MAY DESTROY YOUR DATA (filesystem etc.) Do you really want to reduce centos/home? [y/n]: y Size of logical volume centos/home changed from <41.12 GiB (10526 extents) to 22.00 GiB (5632 extents). Logical volume centos/home successfully resized.
查看卷组信息：
[root@service1 cloud]# vgs VG #PV #LV #SN Attr VSize VFree centos 1 3 0 wz--n- <99.00g 19.12g
# lvextend是扩展逻辑卷，将缩小的22G逻辑卷扩展到根目录分区的逻辑卷中.
[root@service1 cloud]# lvextend -L +19G /dev/mapper/centos-root Size of logical volume centos/root changed from 50.00 GiB (12800 extents) to 69.00 GiB (17664 extents). Logical volume centos/root successfully resized.
#因为根目录的文件系统类型为xfs文件类型，使用xfs_growfs同步根分区.
[root@service1 cloud]# xfs_growfs /dev/centos/root meta-data=/dev/mapper/centos-root isize=512 agcount=4, agsize=3276800 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0 spinodes=0 data = bsize=4096 blocks=13107200, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal bsize=4096 blocks=6400, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 data blocks changed from 13107200 to 18087936 [root@service1 cloud]#
#查看后发现，根分区的目录以扩展了19G.
#由于home目录也是xfs文件类型，所以需要将home目录卸载到重新格式化成xfs，然后再挂载即可.
#格式化为xfs文件系统并重新挂载.
mkfs.xfs -f /dev/mapper/centos-home mount /dev/mapper/centos-home /home # [root@service1 cloud]# df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/mapper/centos-root xfs 69G 1006M 68G 2% / devtmpfs devtmpfs 7.8G 0 7.8G 0% /dev tmpfs tmpfs 7.8G 0 7.8G 0% /dev/shm tmpfs tmpfs 7.8G 9.2M 7.8G 1% /run tmpfs tmpfs 7.8G 0 7.8G 0% /sys/fs/cgroup /dev/xvda1 xfs 1014M 145M 870M 15% /boot tmpfs tmpfs 1.6G 0 1.6G 0% /run/user/0 /dev/mapper/centos-home xfs 22G 33M 22G 1% /home [root@service1 cloud]#