安裝LVM
默認情況下Redhat Linux系統中是默認安裝了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 ~]#
通過查詢可以知道LVM需要lvm2-2.02.56-8.el5及system-config-lvm-1.1.5-4.el5兩個安裝包的支持,如果沒有安裝一下就可以了。
LVM實驗:動態擴展系統分區
新增一塊硬盤,在系統不停機的情況下分配1G空間給系統LogVol00,對系統分區進行擴容,並且保證原有文件不會丟失。
這個要求在windows系統下士沒辦法實現的,但是通過Linux的LVM就可以非常容易實現。
先看下原有系統分區
[root@a ~]# df
文件系統 1K-塊 已用 可用 已用% 掛載點
/dev/mapper/VolGroup00-LogVol00
6983168 2909812 3712908 44% /
系統分區的VG是VolGroup00,VL是LogVol00
這裏我們增加一塊硬盤/dev/sdb
將/dev/sdb建立爲pv
[root@a ~]# pvcreate /dev/sdb
Physical volume "/dev/sdb" successfully created
由於系統已經有了VG:VolGroup00,這裏直接將新建的pv加入到系統VG:VolGroup00
[root@a ~]# vgextend VolGroup00 /dev/sdb
Volume group "VolGroup00" successfully extended
給LogVol00系統LV增加1G的空間
[root@a ~]# lvextend -L +1G /dev/VolGroup00/LogVol00
Extending logical volume LogVol00 to 7.88 GB
Logical volume LogVol00 successfully resized
LV擴容之後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.
查看擴容之後的系統分區
[root@a ~]# df -l
文件系統 1K-塊 已用 可用 已用% 掛載點
/dev/mapper/VolGroup00-LogVol00
7998912 2909816 4676232 39% /
/掛載點的總容量增加了1G,擴容成功
再來查看VolGroup00參數
[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 //還有剩餘空間可以分配
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 --- //在這個VG中有兩塊物理硬盤
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