Dbabc.Net

上接Linux的LVM管理（一）—基本知识和创建 ，VG情况如下

[root@dbabc.net /]# vgscan -v
Wiping cache of LVM-capable devices
Wiping internal VG cache
Reading all physical volumes.  This may take a while...
Finding all volume groups
Finding volume group "vg01"
Found volume group "vg01" using metadata type lvm2
Finding volume group "vg00"
Found volume group "vg00" using metadata type lvm2

先制作一个vg01下的lvol2空间用完的场景，使/test03使用率达到100%：

[root@dbabc.net ~]# df -h
Filesystem                 Size   Used   Avail   Use%  Mounted on
/dev/mapper/vg00-lv_root    6.0G   396M   5.3G    7%   /
/dev/mapper/vg00-lv_usr     6.8G   1.7G    4.8G   26%  /usr
/dev/mapper/vg00-lv_data    93M   5.6M     83M    7%   /data
/dev/sdc1                  988M   24M    914M    3%   /boot
/dev/mapper/vg01-lvol0       4.0G  137M    3.7G    4%   /test01
/dev/mapper/vg01-lvol1       1.9G    35M    1.7G    2%   /test02
/dev/mapper/vg01-lvol2      109M  109M       0   100%   /test03

硬盘情况同上一篇一样，只是剩余sdg未使用，此处用fdisk查看，做pv的硬盘因为并不是直接往单个硬盘里写数据，所以并不会显示使用情况。

[root@dbabc.net ~]# fdisk -l

Disk /dev/sda: 8589 MB, 8589934592 bytes
255 heads, 63 sectors/track, 1044 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        1044     8385898+  8e  Linux LVM

Disk /dev/sdb: 8589 MB, 8589934592 bytes
255 heads, 63 sectors/track, 1044 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *           1        1044     8385898+  8e  Linux LVM

Disk /dev/sdc: 1073 MB, 1073741824 bytes
255 heads, 63 sectors/track, 130 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot      Start         End      Blocks   Id  System
/dev/sdc1   *           1         130     1044193+  83  Linux

Disk /dev/sdd: 2147 MB, 2147483648 bytes
255 heads, 63 sectors/track, 261 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

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

Disk /dev/sde: 2147 MB, 2147483648 bytes
255 heads, 63 sectors/track, 261 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

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

Disk /dev/sdf: 2147 MB, 2147483648 bytes
255 heads, 63 sectors/track, 261 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

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

Disk /dev/sdg: 2147 MB, 2147483648 bytes
255 heads, 63 sectors/track, 261 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

要在线扩容，如果vg01还有未使用的空间的话直接扩展即可，如果没有未使用空间的话，则需要添加新的PV到vg01,此处将sdg做为一个PV后，扩展到vg01,此处无可用空间，所以先把/dev/sdg加入vg01后再扩展

[root@dbabc.net ~]# pvcreate /dev/sdg
Physical volume "/dev/sdg" successfully created
[root@dbabc.net ~]# vgextend vg01 /dev/sdg
Volume group "vg01" successfully extended

新加入一个PV后，此时查看vg01包含四个PV，多出来了刚增加的/dev/sdg：

[root@dbabc.net ~]# vgdisplay -v vg01
Using volume group(s) on command line
Finding volume group "vg01"
--- Volume group ---
VG Name               vg01
System ID
Format                lvm2
Metadata Areas        4
Metadata Sequence No  9
VG Access             read/write
VG Status             resizable
MAX LV                0
Cur LV                3
Open LV               3
Max PV                0
Cur PV                4
Act PV                4
VG Size               7.98 GB
PE Size               4.00 MB
Total PE              2044
Alloc PE / Size       1527 / 5.96 GB
Free  PE / Size       517 / 2.02 GB
VG UUID               t13Ltu-D9vh-nh78-UwEa-Ho7Q-Zo0o-F2JZfJ

--- Logical volume ---
LV Name                /dev/vg01/lvol0
VG Name                vg01
LV UUID                DX3lXF-XK3Z-mj2Y-yMnS-Ns1z-8dt4-542pId
LV Write Access        read/write
LV Status              available
# open                 1
LV Size                4.00 GB
Current LE             1024
Segments               3
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           253:4

--- Logical volume ---
LV Name                /dev/vg01/lvol1
VG Name                vg01
LV UUID                kFtxX7-2TyK-q8wT-e3cu-TfkE-NEcN-lAtFI7
LV Write Access        read/write
LV Status              available
# open                 1
LV Size                1.86 GB
Current LE             475
Segments               1
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           253:5

--- Logical volume ---
LV Name                /dev/vg01/lvol2
VG Name                vg01
LV UUID                kmPX21-6F9M-LCuI-Gpxq-nHvV-1kcT-WuYyHT
LV Write Access        read/write
LV Status              available
# open                 1
LV Size                112.00 MB
Current LE             28
Segments               1
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           253:6

--- Physical volumes ---
PV Name               /dev/sdd
PV UUID               wd8Vy3-Uln9-PyA8-pAcr-2Cj7-D9eF-CVYoDN
PV Status             allocatable
Total PE / Free PE    511 / 0

PV Name               /dev/sde
PV UUID               2zC9un-1K60-J81Z-LPr6-42Vz-CGl7-cgoA3m
PV Status             allocatable
Total PE / Free PE    511 / 0

PV Name               /dev/sdf
PV UUID               j0LIlX-e3yQ-cgGA-ia2v-Ws6v-3QNW-xg8z21
PV Status             allocatable
Total PE / Free PE    511 / 6

PV Name               /dev/sdg
PV UUID               2GG5b0-bzyn-1TYQ-H3DB-RvGC-2QuD-H1oEHk
PV Status             allocatable
Total PE / Free PE    511 / 511

用lvresize命令将此VG中未使用的空间扩展到lvol2，以下是增加1024M。

[root@dbabc.net ~]# lvresize -L+1024 /dev/vg01/lvol2
Extending logical volume lvol2 to 1.11 GB
Logical volume lvol2 successfully resized

再看df的状态，/test03使用率仍为100%，因为lvresize只是做一个扩展的映射，并未真正扩展到lv上面。

[root@dbabc.net ~]# df -h
Filesystem                           Size   Used   Avail  Use%  Mounted on
/dev/mapper/vg00-lv_root   6.0G  396M   5.3G    7%     /
/dev/mapper/vg00-lv_usr    6.8G   1.7G   4.8G   26%    /usr
/dev/mapper/vg00-lv_data   93M   5.6M    83M    7%     /data
/dev/sdc1                  988M    24M  914M    3%     /boot
/dev/mapper/vg01-lvol0      4.0G   137M  3.7G    4%     /test01
/dev/mapper/vg01-lvol1      1.9G     35M  1.7G    2%     /test02
/dev/mapper/vg01-lvol2     109M   109M       0  100%    /test03

要将扩展完成，需要一个resize2fs的命令，令新增的空间在线（on-line）生效。

[root@dbabc.net ~]# resize2fs /dev/vg01/lvol2
resize2fs 1.39 (29-May-2006)
Filesystem at /dev/vg01/lvol2 is mounted on /test03; on-line resizing required
Performing an on-line resize of /dev/vg01/lvol2 to 1163264 (1k) blocks.
The filesystem on /dev/vg01/lvol2 is now 1163264 blocks long.

再查看/test03目录的大小：

[root@dbabc.net ~]# df -h
Filesystem                           Size   Used  Avail  Use%  Mounted on
/dev/mapper/vg00-lv_root   6.0G  398M  5.3G   7%     /
/dev/mapper/vg00-lv_usr     6.8G  1.7G   4.8G  26%   /usr
/dev/mapper/vg00-lv_data     93M  5.6M   83M   7%    /data
/dev/sdc1                   988M   24M  914M   3%   /boot
/dev/mapper/vg01-lvol0        4.0G  137M  3.7G   4%   /test01
/dev/mapper/vg01-lvol1        1.9G   35M  1.7G    2%   /test02
/dev/mapper/vg01-lvol2        1.1G  110M  934M  11%  /test03

查看lvol2的信息，可看到空间变大了。

[root@dbabc.net ~]# lvdisplay -v /dev/vg01/lvol2
Using logical volume(s) on command line
--- Logical volume ---
LV Name                /dev/vg01/lvol2
VG Name                vg01
LV UUID                kmPX21-6F9M-LCuI-Gpxq-nHvV-1kcT-WuYyHT
LV Write Access        read/write
LV Status              available
# open                 1
LV Size                1.11 GB
Current LE             284
Segments               2
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           253:6