【Linux】lvm基础操作

新增两块硬盘,来进行实验：

[root@jp ~]# fdisk -l

Disk /dev/sda: 107.3 GB, 107374182400 bytes
255 heads, 63 sectors/track, 13054 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 255 2048256 83 Linux
/dev/sda2 256 777 4192965 82 Linux swap / Solaris
/dev/sda3 778 13054 98615002+ 83 Linux

Disk /dev/sdb: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdb doesn't contain a valid partition table

Disk /dev/sdc: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdc doesn't contain a valid partition table
随便将/dev/sdb分成三个区

[root@jp ~]# fdisk /dev/sdb
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.

Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-652, default 1): 1
Last cylinder or +size or +sizeM or +sizeK (1-652, default 652): +1000M

Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 2
First cylinder (124-652, default 124):
Using default value 124
Last cylinder or +size or +sizeM or +sizeK (124-652, default 652): +2000M

Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 3
First cylinder (368-652, default 368):
Using default value 368
Last cylinder or +size or +sizeM or +sizeK (368-652, default 652):
Using default value 652

Command (m for help): p

Disk /dev/sdb: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 1 123 987966 83 Linux
/dev/sdb2 124 367 1959930 83 Linux
/dev/sdb3 368 652 2289262+ 83 Linux

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.

/dev/sdc随便分两个区：

[root@jp ~]# fdisk /dev/sdc
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.

Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-652, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-652, default 652): +2000M

Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 2
First cylinder (245-652, default 245):
Using default value 245
Last cylinder or +size or +sizeM or +sizeK (245-652, default 652):
Using default value 652

Command (m for help): p

Disk /dev/sdc: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdc1 1 244 1959898+ 83 Linux
/dev/sdc2 245 652 3277260 83 Linux

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

将所有分区创建PV

[root@jp ~]# pvcreate /dev/sdb1
Physical volume "/dev/sdb1" successfully created
[root@jp ~]# pvcreate /dev/sdb2
Physical volume "/dev/sdb2" successfully created
[root@jp ~]# pvcreate /dev/sdb3
Physical volume "/dev/sdb3" successfully created
[root@jp ~]# pvcreate /dev/sdc1
Physical volume "/dev/sdc1" successfully created
[root@jp ~]# pvcreate /dev/sdc2
Physical volume "/dev/sdc2" successfully created

创建VG，将/dev/sdb1和/dev/sdc1放到该VG中

[root@jp ~]# vgcreate test1 /dev/sdb1 /dev/sdc1
/dev/cdrom: open failed: No medium found
Volume group "test1" successfully created
向VG中增加磁盘：

[root@jp ~]# vgextend test1 /dev/sdb2
Volume group "test1" successfully extended
查看VG信息：

[root@jp ~]# vgdisplay
--- Volume group ---
VG Name test1
System ID
Format lvm2
Metadata Areas 3
Metadata Sequence No 4
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 3
Act PV 3
VG Size 4.68 GB
PE Size 4.00 MB
Total PE 1197
Alloc PE / Size 300 / 1.17 GB
Free PE / Size 897 / 3.50 GB
VG UUID 0ux9KE-yHJP-07Y0-9yCd-ppG2-wWe0-78nLbh

创建LV，从VG：test1中拿出1000M给该LV：lv_test1

[root@jp ~]# lvcreate -L 1000M -n lv_test1 test1
Logical volume "lv_test1" created
格式化LV，LV只有在格式化之后才能存储数据

[root@jp ~]# mke2fs -j /dev/test1/lv_test1
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
128000 inodes, 256000 blocks
12800 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=264241152
8 block groups
32768 blocks per group, 32768 fragments per group
16000 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376

Writing inode tables: done
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 33 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
挂载LV：

[root@jp ~]# mkdir /test
[root@jp ~]# mount /dev/test1/lv_test1 /test
[root@jp ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda3 92G 20G 67G 23% /
/dev/sda1 1.9G 42M 1.8G 3% /boot
tmpfs 1014M 0 1014M 0% /dev/shm
/dev/mapper/test1-lv_test1
985M 18M 918M 2% /test
挂载之后，可以但到此LV的容量。

如果要在系统启动的时候启动LV，最好是将LV01写入fstable文件中

调整LV的大小

[root@jp ~]# lvresize -L +200M /dev/test1/lv_test1
Extending logical volume lv_test1 to 1.17 GB
Logical volume lv_test1 successfully resized

[root@jp ~]# resize2fs /dev/test1/lv_test1
resize2fs 1.39 (29-May-2006)
Filesystem at /dev/test1/lv_test1 is mounted on /test; on-line resizing required
Performing an on-line resize of /dev/test1/lv_test1 to 307200 (4k) blocks.
The filesystem on /dev/test1/lv_test1 is now 307200 blocks long.