How to extend logical volume space (给逻辑卷扩展空间)

How to extend logical volume space (给逻辑卷扩展空间)

1. 新增硬盘

在VM上给相应客户机添加新硬盘（本次新增的硬盘空间为100G）

在客户机上操作/proc/scsi/scsi文件，使硬盘能够被认到（如果可以重启，请或略此步骤）

[root@hz-jenkins scsi]# pwd
/proc/scsi
[root@hz-jenkins scsi]# echo "scsi add-single-device 2 0 1 0" > /proc/scsi/scsi
# 查看 scsi文件，最后那个设备就是新增的
[root@hz-jenkins scsi]# cat scsi
Attached devices:
Host: scsi1 Channel: 00 Id: 00 Lun: 00
Vendor: NECVMWar Model: VMware IDE CDR10 Rev: 1.00
Type:   CD-ROM                           ANSI  SCSI revision: 05
Host: scsi2 Channel: 00 Id: 00 Lun: 00
Vendor: VMware   Model: Virtual disk     Rev: 1.0
Type:   Direct-Access                    ANSI  SCSI revision: 02
Host: scsi2 Channel: 00 Id: 01 Lun: 00
Vendor: VMware   Model: Virtual disk     Rev: 1.0
Type:   Direct-Access                    ANSI  SCSI revision: 02

备注：

“scsi add-single-device x y z u”中，x, y, z, u 分别是指以下的2 0 1 0

Host: scsi2 Channel: 00 Id: 01 Lun: 00

检查是否成功，可以通过fdisk -l或者查看/dev/sd?进行查看

[root@hz-jenkins scsi]# fdisk -l
..
Disk /dev/sdb: 100 GiB, 107374182400 bytes, 209715200 sectors
..
[root@hz-jenkins scsi]# ll /dev/sd?
brw-rw---- 1 root disk 8,  0 Dec  1 11:01 /dev/sda
brw-rw---- 1 root disk 8, 16 Dec  1 16:35 /dev/sdb
[root@hz-jenkins scsi]# fdisk -l

2. 创建硬盘分区

（此处建3个主分区，Type为8e，大小分别为40G, 40G, 20G，目的是为了空间不用时可以收回）

[root@hz-jenkins scsi]# fdisk /dev/sdb
..
# 创建后，可以看到/dev/sdb1,2,3三个块文件
[root@hz-jenkins scsi]# ll /dev/sdb*
brw-rw---- 1 root disk 8, 16 Dec  1 16:42 /dev/sdb
brw-rw---- 1 root disk 8, 17 Dec  1 16:43 /dev/sdb1
brw-rw---- 1 root disk 8, 18 Dec  1 16:43 /dev/sdb2
brw-rw---- 1 root disk 8, 19 Dec  1 16:43 /dev/sdb3

3. 创建PV

[root@hz-jenkins ~]# pvcreate /dev/sdb?
Physical volume "/dev/sdb1" successfully created
Physical volume "/dev/sdb2" successfully created
Physical volume "/dev/sdb3" successfully created
[root@hz-jenkins ~]# pvdisplay
...
"/dev/sdb3" is a new physical volume of "20.00 GiB"
--- NEW Physical volume ---
PV Name               /dev/sdb3
VG Name
PV Size               20.00 GiB
Allocatable           NO
PE Size               0
Total PE              0
Free PE               0
Allocated PE          0
PV UUID               ApvQgx-olTW-dODR-jztk-0NZJ-HnZa-Tp1d9L
..
"/dev/sdb2" is a new physical volume of "40.00 GiB"
..
"/dev/sdb1" is a new physical volume of "40.00 GiB"
..

创建PV后，可以通过pvdisplay查看到新增的3个pv的详细信息

4. 扩展VG

[root@hz-jenkins scsi]# vgextend fedora /dev/sdb[1-3]
Volume group "fedora" successfully extended
[root@hz-jenkins scsi]# vgdisplay
..
VG Size               199.50 GiB
PE Size               4.00 MiB
Total PE              51071
Alloc PE / Size       25474 / 99.51 GiB
Free  PE / Size       25597 / 99.99 GiB
VG UUID               XGkRbq-lWNj-6jVp-1T52-eaEi-2yGC-guOm75
[root@hz-jenkins scsi]#

扩展后，通过vgdisplay命令可以看到，新增的Free Size 为99.99GiB

5. 扩展LV

通过 pvdisplay, vgdisplay 可以查看有多少空间（或多少PE数）可以使用

[root@hz-jenkins scsi]# pvdisplay
..
--- Physical volume ---
PV Name               /dev/sdb1
VG Name               fedora
PV Size               40.00 GiB / not usable 4.00 MiB
Allocatable           yes
PE Size               4.00 MiB
Total PE              10239
Free PE               10239
Allocated PE          0
PV UUID               KRvzJZ-l7xp-IdrL-3QbQ-8bHN-sPnU-OWSy7G

--- Physical volume ---
PV Name               /dev/sdb2
Total PE              10239
Free PE               10239
Allocated PE          0
..
--- Physical volume ---
PV Name               /dev/sdb3
Total PE              5119
Free PE               5119
Allocated PE          0
..

接下去进行lv扩展，使用lvresize命令（此处先扩大40G，按/dev/sdb1的大小10239个PE）

[root@hz-jenkins scsi]# lvresize -l +10239 /dev/fedora/home
Extending logical volume home to 59.53 GiB
Logical volume home successfully resized
[root@hz-jenkins scsi]# df -vh

使用resize2fs命令，使lv空间更改生效

[root@hz-jenkins scsi]# df -vh /home
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/fedora-home   20G   18G  546M  98% /home

[root@hz-jenkins scsi]# resize2fs /dev/fedora/home
resize2fs 1.42.12 (29-Aug-2014)
Filesystem at /dev/fedora/home is mounted on /home; on-line resizing required
old_desc_blocks = 2, new_desc_blocks = 4
The filesystem on /dev/fedora/home is now 15604736 (4k) blocks long.

[root@hz-jenkins scsi]# df -vh /home
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/fedora-home   59G   18G   39G  32% /home
#

备注：

以上vg name: fedora, lv name: home命名不是很好

一般vg name用vg_开头，lv name用lv_开头，所以更好的命名应该为 vg_fedora, lv_home

把剩下的60G（/dev/sdb2, /dev/sdb3）也扩进/home

10239+5119=15358

[root@hz-jenkins ~]# lvresize -l +15358 /dev/fedora/home
Extending logical volume home to 119.52 GiB
Logical volume home successfully resized

[root@hz-jenkins ~]# df -vh /home
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/fedora-home   59G   18G   39G  32% /home

[root@hz-jenkins ~]# resize2fs /dev/fedora/home
resize2fs 1.42.12 (29-Aug-2014)
Filesystem at /dev/fedora/home is mounted on /home; on-line resizing required
old_desc_blocks = 4, new_desc_blocks = 8
The filesystem on /dev/fedora/home is now 31331328 (4k) blocks long.

[root@hz-jenkins ~]# df -vh /home
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/fedora-home  118G   18G   95G  16% /home
[root@hz-jenkins ~]#

参考文档：

1. LVM 理论与实践

http://vbird.dic.ksu.edu.tw/linux_basic/0420quota_3.php

2. Linux不重启添加识别硬盘

http://www.myhack58.com/Article/48/66/2015/66573.htm

http://blog.itpub.net/7348112/viewspace-765000/