逻辑卷扩容

安装LVM

默认情况下Redhat Linux系统中是默认安装了lvm工具的

[root@a ~]# rpm -qa |grep lvm

lvm2-2.02.56-8.el5

system-config-lvm-1.1.5-4.el5

[root@a ~]#

通过查询可以知道LVM需要lvm2-2.02.56-8.el5及system-config-lvm-1.1.5-4.el5两个安装包的支持，如果没有安装一下就可以了。

LVM实验：动态扩展系统分区

新增一块硬盘，在系统不停机的情况下分配1G空间给系统LogVol00，对系统分区进行扩容，并且保证原有文件不会丢失。

这个要求在windows系统下士没办法实现的，但是通过Linux的LVM就可以非常容易实现。

先看下原有系统分区

[root@a ~]# df

文件系统 1K-块 已用 可用 已用% 挂载点

/dev/mapper/VolGroup00-LogVol00

6983168 2909812 3712908 44% /

系统分区的VG是VolGroup00，VL是LogVol00

这里我们增加一块硬盘/dev/sdb

将/dev/sdb建立为pv

[root@a ~]# pvcreate /dev/sdb

Physical volume "/dev/sdb" successfully created

由于系统已经有了VG：VolGroup00，这里直接将新建的pv加入到系统VG：VolGroup00

[root@a ~]# vgextend VolGroup00 /dev/sdb

Volume group "VolGroup00" successfully extended

给LogVol00系统LV增加1G的空间

[root@a ~]# lvextend -L +1G /dev/VolGroup00/LogVol00

Extending logical volume LogVol00 to 7.88 GB

Logical volume LogVol00 successfully resized

LV扩容之后需要激活修改的配置

[root@a ~]# resize2fs /dev/VolGroup00/LogVol00

resize2fs 1.39 (29-May-2006)

Filesystem at /dev/VolGroup00/LogVol00 is mounted on /; on-line resizing required

Performing an on-line resize of /dev/VolGroup00/LogVol00 to 2064384 (4k) blocks.

The filesystem on /dev/VolGroup00/LogVol00 is now 2064384 blocks long.

查看扩容之后的系统分区

[root@a ~]# df -l

文件系统 1K-块 已用 可用 已用% 挂载点

/dev/mapper/VolGroup00-LogVol00

7998912 2909816 4676232 39% /

/挂载点的总容量增加了1G，扩容成功

再来查看VolGroup00参数

[root@a ~]# vgdisplay -v VolGroup00

Using volume group(s) on command line

Finding volume group "VolGroup00"

--- Volume group ---

VG Name VolGroup00

System ID

Format lvm2

Metadata Areas 2

Metadata Sequence No 7

VG Access read/write

VG Status resizable

MAX LV 0

Cur LV 2

Open LV 2

Max PV 0

Cur PV 2

Act PV 2

VG Size 10.84 GB

PE Size 32.00 MB

Total PE 347

Alloc PE / Size 284 / 8.88 GB

Free PE / Size 63 / 1.97 GB //还有剩余空间可以分配

VG UUID vPFrNV-lcZz-ZiAA-oZpt-VqWZ-gIC3-RCuJG7

--- Logical volume ---

LV Name /dev/VolGroup00/LogVol00

VG Name VolGroup00

LV UUID 9QP8xz-w6dQ-luU0-y52W-1vct-1BvG-zKjLO8

LV Write Access read/write

LV Status available

# open 1

LV Size 7.88 GB

Current LE 252

Segments 2

Allocation inherit

Read ahead sectors auto

- currently set to 256

Block device 253:0

--- Logical volume ---

LV Name /dev/VolGroup00/LogVol01

VG Name VolGroup00

LV UUID DWTtvU-SwNi-6Vho-HetD-O2a0-hSRV-F8AYi1

LV Write Access read/write

LV Status available

# open 1

LV Size 1.00 GB

Current LE 32

Segments 1

Allocation inherit

Read ahead sectors auto

- currently set to 256

Block device 253:1

--- Physical volumes --- //在这个VG中有两块物理硬盘

PV Name /dev/sda2

PV UUID 594r8z-ROTL-2VBc-DPlr-f4iG-Blx5-Vu1I81

PV Status allocatable

Total PE / Free PE 252 / 0

PV Name /dev/sdb

PV UUID 1R1H2t-f2DP-hYCQ-hkBE-HtmD-2kZy-2Bj4TY

PV Status allocatable

Total PE / Free PE 95 / 63