linux上lvm扩容

1--创建LVM分区

方法和创建其他一般分区的方式是一样的，区别仅仅是LVM的分区类型为8e.

查看已有分区

使用fdisk创建分区，根据设备文件的绝对路径（/dev/）进入分区管理

fdisk /dev/sdb

[root@test149 ~]# fdisk /dev/sdb

WARNING: DOS-compatible mode is deprecated. It's strongly recommended to

switch off the mode (command 'c') and change display units to

sectors (command 'u').

Command (m for help): p--查看分区信息

Disk /dev/sdb: 10.7 GB, 10737418240 bytes

255 heads, 63 sectors/track, 1305 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x29af97f8

Device Boot Start End Blocks Id System

Command (m for help): n--新建分区

Command action

e extended

p primary partition (1-4)

p --选择分区类型为主分区

Partition number (1-4): 1--分区号为1

First cylinder (1-1305, default 1): --使用默认值

Using default value 1

Last cylinder, +cylinders or +size{K,M,G} (1-1305, default 1305): --使用默认值（最大值）

Using default value 1305

Command (m for help): p--查看分区信息

Disk /dev/sdb: 10.7 GB, 10737418240 bytes

255 heads, 63 sectors/track, 1305 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x29af97f8

Device Boot Start End Blocks Id System

/dev/sdb1 1 1305 10482381 83 Linux

Command (m for help): t --修改分区格式

Selected partition 1 --这里需要指定分区，只有一个默认选1

Hex code (type L to list codes): 8e --类型改为8e,LVM

Changed system type of partition 1 to 8e (Linux LVM)

Command (m for help): p--查看当前分区

Disk /dev/sdb: 10.7 GB, 10737418240 bytes

255 heads, 63 sectors/track, 1305 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x29af97f8

Device Boot Start End Blocks Id System

/dev/sdb1 1 1305 10482381 8e Linux LVM

Command (m for help): w --保存

The partition table has been altered!

Calling ioctl() to re-read partition table.

Syncing disks.

[root@gm149 ~]# fdisk -l /dev/sdb

Disk /dev/sdb: 10.7 GB, 10737418240 bytes

255 heads, 63 sectors/track, 1305 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x29af97f8

Device Boot Start End Blocks Id System

/dev/sdb1 1 1305 10482381 8e Linux LVM

一定要指定分区的格式为8e，这是LVM的分区格式

[root@gm149 ~]# partprobe --使分区表生效，无需重启

2—格式化

查看格式化信息

将新的磁盘格式化

[root@gm149 /]# mkfs -t ext4 /dev/sdb1

mke2fs 1.41.12 (17-May-2010)

Filesystem label=

OS type: Linux

Block size=4096 (log=2)

Fragment size=4096 (log=2)

Stride=0 blocks, Stripe width=0 blocks

655360 inodes, 2620595 blocks

131029 blocks (5.00%) reserved for the super user

First data block=0

Maximum filesystem blocks=2684354560

80 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

Writing inode tables: done

Creating journal (32768 blocks): done

Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 23 mounts or

180 days, whichever comes first. Use tune2fs -c or -i to override.

[root@gm149 /]#

#查看硬盘的分区表及使用情况

[root@gm149 /]# partx /dev/sdb

# 1: 63- 20964824 ( 20964762 sectors, 10733 MB)

# 2: 0- -1 ( 0 sectors, 0 MB)

# 3: 0- -1 ( 0 sectors, 0 MB)

# 4: 0- -1 ( 0 sectors, 0 MB)

3—创建物理卷PV à逻辑卷组 VG à逻辑卷LV

pvdisplay --查看物理卷PV

也可以使用pvs查看PV

[root@gm149 /]# pvs --查看PV

PV VG Fmt Attr PSize PFree

/dev/sda2 vg_gm149 lvm2 a--u 49.75g 0

查看系统的逻辑卷组vg和逻辑卷lv

[root@gm149 ~]# vgs --查看逻辑卷组vg

VG #PV #LV #SN Attr VSize VFree

vg_gm149 1 2 0 wz--n- 49.75g 0

[root@gm149 ~]# lvs --查看逻辑卷lv

LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert

lv_oracle_data vg_gm149 -wi-ao---- 41.84g

lv_swap vg_gm149 -wi-ao---- 7.90g

或者使用vgdisplay和lvdisplay

创建PV

[root@gm149 /]# pvcreate /dev/sdb1 --创建新的物理卷PV

Physical volume "/dev/sdb1" successfully created

[root@gm149 /]# pvdisplay --查看物理卷PV

--- Physical volume ---

PV Name /dev/sda2

VG Name vg_gm149

PV Size 49.75 GiB / not usable 3.00 MiB

Allocatable yes (but full)

PE Size 4.00 MiB

Total PE 12735

Free PE 0

Allocated PE 12735

PV UUID XGyuAh-ZnzL-i7Mo-NULN-B7g1-MTiQ-k6goqM

"/dev/sdb1" is a new physical volume of "10.00 GiB"

--- NEW Physical volume ---

PV Name /dev/sdb1

VG Name

PV Size 10.00 GiB

Allocatable NO

PE Size 0

Total PE 0

Free PE 0

Allocated PE 0

PV UUID sY4qe3-djgI-eBm6-SqFk-X1Bo-JmpL-FSclOz

[root@gm149 /]#

扩容VG

扩展卷组vgextend，将某个物理卷添加到一个已存在的卷组

[root@gm149 ~]# vgs --查看当前的VG信息

VG #PV #LV #SN Attr VSize VFree

vg_gm149 1 2 0 wz--n- 49.75g 0

[root@gm149 /]# vgextend vg_gm149 /dev/sdb1 --扩展当前的VG：vg_gm149

Volume group "vg_gm149" successfully extended

[root@gm149 /]# vgs

VG #PV #LV #SN Attr VSize VFree

vg_gm149 2 2 0 wz--n- 59.74g 9.99g

[root@gm149 /]#

扩容LV

[root@gm149 /]# lvs --查看当前的LV信息

LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert

lv_oracle_data vg_gm149 -wi-ao---- 41.84g

lv_swap vg_gm149 -wi-ao---- 7.90g

[root@gm149 /]# lvextend -L +9.98g /dev/vg_gm149/lv_oracle_data /dev/sdb1 --扩展LV

Rounding size to boundary between physical extents: 9.98 GiB.

Size of logical volume vg_gm149/lv_oracle_data changed from 41.84 GiB (10712 extents) to 51.82 GiB (13267 extents).

Logical volume lv_oracle_data successfully resized.

[root@gm149 /]# lvs

LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert

lv_oracle_data vg_gm149 -wi-ao---- 51.82g

lv_swap vg_gm149 -wi-ao---- 7.90g

使用resize2fs更新系统识别的文件系统大小，立即生效

是增加的逻辑卷立即生效

[root@gm149 oracle]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/vg_gm149-lv_oracle_data

42G 38G 1.4G 97% /

tmpfs 3.9G 2.0G 1.9G 52% /dev/shm

/dev/sda1 240M 73M 155M 32% /boot

[root@gm149 oracle]# resize2fs /dev/vg_gm149/lv_oracle_data

resize2fs 1.41.12 (17-May-2010)

Filesystem at /dev/vg_gm149/lv_oracle_data is mounted on /; on-line resizing required

old desc_blocks = 3, new_desc_blocks = 4

Performing an on-line resize of /dev/vg_gm149/lv_oracle_data to 13585408 (4k) blocks.

The filesystem on /dev/vg_gm149/lv_oracle_data is now 13585408 blocks long.

[root@gm149 oracle]#

删除物理卷

删除卷LVM管理中的命令vgreduce, pvremove：

vgreduce：通过删除LVM卷组中的物理卷来减少卷组容量。注意：不能删除LVM卷组中剩余的最后一个物理卷

pvremove: 用于删除一个存在的物理卷。使用pvremove指令删除物理卷时，它将LVM分区上的物理卷信息删除，使其不再被视为一个物理卷。

[root@gm149 ~]# pvremove /dev/sdb1

Labels on physical volume "/dev/sdb1" successfully wiped

在删除物理卷PV之前，必须将服务器的分区信息、卷组信息、物理卷信息、逻辑卷信息都掌握清楚，避免出现失误或误操作。

参考文档：

http://www.cnblogs.com/gaojun/archive/2012/08/22/2650229.html