LVM test
Did some LVM test, recorded the procedure,
I have a disk having space as 160G, showing as:
[root@localhost ~]# fdisk -l
Disk /dev/sda: 160.0 GB, 160041885696 bytes, 312581808 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x210edd27
Device Boot Start End Blocks Id System
/dev/sda1 2048 83891429 41944691 82 Linux swap / Solaris
/dev/sda2 83891430 167782859 41945715 7 HPFS/NTFS/exFAT
/dev/sda3 167782860 251674289 41945715 7 HPFS/NTFS/exFAT
/dev/sda4 251674290 312576704 30451207+ c W95 FAT32 (LBA)
1, create a VG(volume group), the PE(physical extend) as 16M, name as xiongvg, then add the sda4 to the VG
[root@localhost ~]# vgcreate -s 16M xiongvg /dev/sda{1,2,3}
Volume group "xiongvg" successfully created
[root@localhost ~]# vgscan
Reading all physical volumes. This may take a while...
Found volume group "xiongvg" using metadata type lvm2
[root@localhost ~]# pvscan
PV /dev/sda1 VG xiongvg lvm2 [40.00 GiB / 40.00 GiB free]
PV /dev/sda2 VG xiongvg lvm2 [40.00 GiB / 40.00 GiB free]
PV /dev/sda3 VG xiongvg lvm2 [40.00 GiB / 40.00 GiB free]
PV /dev/sda4 lvm2 [29.04 GiB]
Total: 4 [149.04 GiB] / in use: 3 [120.00 GiB] / in no VG: 1 [29.04 GiB]
[root@localhost ~]# vgdisplay
--- Volume group ---
VG Name xiongvg
System ID
Format lvm2
Metadata Areas 3
Metadata Sequence No 1
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 3
Act PV 3
VG Size 120.00 GiB
PE Size 16.00 MiB
Total PE 7680
Alloc PE / Size 0 / 0
Free PE / Size 7680 / 120.00 GiB
VG UUID grCIPp-lbvS-OLMH-TiQO-mJ0L-zPyR-JIBjfM
[root@localhost ~]# vgextend xiongvg /dev/sda4
Volume group "xiongvg" successfully extended
[root@localhost ~]# vgdisplay
--- Volume group ---
VG Name xiongvg
System ID
Format lvm2
Metadata Areas 4
Metadata Sequence No 2
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 4
Act PV 4
VG Size 149.03 GiB
PE Size 16.00 MiB
Total PE 9538
Alloc PE / Size 0 / 0
Free PE / Size 9538 / 149.03 GiB
VG UUID grCIPp-lbvS-OLMH-TiQO-mJ0L-zPyR-JIBjfM
[root@localhost ~]# pvscan
PV /dev/sda1 VG xiongvg lvm2 [40.00 GiB / 40.00 GiB free]
PV /dev/sda2 VG xiongvg lvm2 [40.00 GiB / 40.00 GiB free]
PV /dev/sda3 VG xiongvg lvm2 [40.00 GiB / 40.00 GiB free]
PV /dev/sda4 VG xiongvg lvm2 [29.03 GiB / 29.03 GiB free]
Total: 4 [149.03 GiB] / in use: 4 [149.03 GiB] / in no VG: 0 [0 ]
2, create a LV(Logical Volume), formatted as file system and mount
[root@localhost ~]# lvcreate -l 356 -n xionglv xiongvg
WARNING: ext3 signature detected on /dev/xiongvg/xionglv at offset 1080. Wipe it? [y/n] y
Wiping ext3 signature on /dev/xiongvg/xionglv.
Logical volume "xionglv" created
[root@localhost ~]# ll /dev/xiongvg/xionglv
lrwxrwxrwx. 1 root root 7 Sep 3 12:28 /dev/xiongvg/xionglv -> ../dm-0
[root@localhost ~]# lvdisplay
--- Logical volume ---
LV Path /dev/xiongvg/xionglv
LV Name xionglv
VG Name xiongvg
LV UUID YDpSjy-Wo6r-JVdx-P4hc-GxNC-O4BQ-bMd9xr
LV Write Access read/write
LV Creation host, time localhost.localdomain, 2014-09-03 12:27:52 +0800
LV Status available
# open 0
LV Size 5.56 GiB
Current LE 356
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
[root@localhost ~]# mkfs -t ext3 /dev/xiongvg/xionglv
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
365040 inodes, 1458176 blocks
72908 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=1493172224
45 block groups
32768 blocks per group, 32768 fragments per group
8112 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
[root@localhost ~]# mkdir /mnt/lvm
[root@localhost ~]# mount /dev/xiongvg/xionglv /mnt/lvm
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sdb7 36G 7.7G 26G 23% /
devtmpfs 908M 0 908M 0% /dev
tmpfs 916M 92K 916M 1% /dev/shm
tmpfs 916M 9.0M 907M 1% /run
tmpfs 916M 0 916M 0% /sys/fs/cgroup
/dev/sdb6 190M 169M 7.1M 96% /boot
/dev/mapper/xiongvg-xionglv 5.4G 12M 5.1G 1% /mnt/lvm
3, LV size enlarge, LV size reduce
[root@localhost ~]# lvresize -l +179 /dev/xiongvg/xionglv
Extending logical volume xionglv to 8.36 GiB
Logical volume xionglv successfully resized
[root@localhost ~]# df /mnt/lvm
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/mapper/xiongvg-xionglv 5609948 11516 5290416 1% /mnt/lvm
make change to the file system,
[root@localhost ~]# resize2fs /dev/xiongvg/xionglv
resize2fs 1.42.9 (28-Dec-2013)
Filesystem at /dev/xiongvg/xionglv is mounted on /mnt/lvm; on-line resizing required
old_desc_blocks = 1, new_desc_blocks = 1
The filesystem on /dev/xiongvg/xionglv is now 2191360 blocks long.
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sdb7 36G 7.7G 26G 23% /
devtmpfs 908M 0 908M 0% /dev
tmpfs 916M 92K 916M 1% /dev/shm
tmpfs 916M 9.0M 907M 1% /run
tmpfs 916M 0 916M 0% /sys/fs/cgroup
/dev/sdb6 190M 169M 7.1M 96% /boot
/dev/mapper/xiongvg-xionglv 8.2G 13M 7.7G 1% /mnt/lvm
[root@localhost ~]#
[root@localhost ~]# resize2fs /dev/xiongvg/xionglv 6900M
resize2fs 1.42.9 (28-Dec-2013)
Filesystem at /dev/xiongvg/xionglv is mounted on /mnt/lvm; on-line resizing required
resize2fs: On-line shrinking not supported
[root@localhost ~]# umount /mnt/lvm
[root@localhost ~]# resize2fs /dev/xiongvg/xionglv 6900M
resize2fs 1.42.9 (28-Dec-2013)
Please run 'e2fsck -f /dev/xiongvg/xionglv' first.
[root@localhost ~]# e2fsck -f /dev/xiongvg/xionglv
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/xiongvg/xionglv: 11/543504 files (0.0% non-contiguous), 70123/2191360 blocks
[root@localhost ~]# resize2fs /dev/xiongvg/xionglv 6900M
resize2fs 1.42.9 (28-Dec-2013)
Resizing the filesystem on /dev/xiongvg/xionglv to 1766400 (4k) blocks.
The filesystem on /dev/xiongvg/xionglv is now 1766400 blocks long.
[root@localhost ~]# mount /dev/xiongvg/xionglv /mnt/lvm
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sdb7 36G 7.7G 26G 23% /
devtmpfs 908M 0 908M 0% /dev
tmpfs 916M 92K 916M 1% /dev/shm
tmpfs 916M 9.0M 907M 1% /run
tmpfs 916M 0 916M 0% /sys/fs/cgroup
/dev/sdb6 190M 169M 7.1M 96% /boot
/dev/mapper/xiongvg-xionglv 6.6G 13M 6.2G 1% /mnt/lvm