===== 为Xen虚拟机扩容根文件系统(LVM) =====
1. 增加1个4G的映像文件
# dd if=/dev/zero of=data.img bs=4k seek=1024k count=1
2. 更改虚拟机配置：
disk = [ "tap:aio:/xen_images/xen_centos6.5x64/centos6.5x64.img,xvda,w",
"tap:aio:/xen_images/xen_centos6.5x64/data.img,xvdb,w" ]
3. 查看LINUX的PV,VG和LV信息：
[root@server1 ~]# pvdisplay
--- Physical volume ---
PV Name /dev/xvda2
VG Name VolGroup00
PV Size 15.90 GB / not usable 20.79 MB
Allocatable yes (but full)
PE Size (KByte) 32768
Total PE 508
Free PE 0
Allocated PE 508
PV UUID AQLigU-Kra3-qXIU-ul0J-flmS-cB5j-RfAaEv
[root@server1 ~]# vgdisplay
--- Volume group ---
VG Name VolGroup00
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 3
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 1
Act PV 1
VG Size 15.88 GB
PE Size 32.00 MB
Total PE 508
Alloc PE / Size 508 / 15.88 GB
Free PE / Size 0 / 0
VG UUID FbUuvN-yE0U-cRkA-fOL0-aIRP-eHdG-TzDN5P
[root@server1 ~]# lvdisplay
--- Logical volume ---
LV Name /dev/VolGroup00/LogVol00
VG Name VolGroup00
LV UUID bLPTMQ-3TlN-1pIO-vKUv-oU9A-mYnh-dLdqFF
LV Write Access read/write
LV Status available
# open 1
LV Size 13.84 GB
Current LE 443
Segments 1
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 YDw1jP-eF7K-Yrms-H0QD-4f7p-oPMv-PeXqrO
LV Write Access read/write
LV Status available
# open 1
LV Size 2.03 GB
Current LE 65
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:1
4. 将新增的硬盘/dev/xvdb创建为PV
[root@server1 ~]# pvcreate /dev/xvdb
Physical volume "/dev/xvdb" successfully created
[root@server1 ~]# pvdisplay
--- Physical volume ---
PV Name /dev/xvda2
VG Name VolGroup00
PV Size 15.90 GB / not usable 20.79 MB
Allocatable yes (but full)
PE Size (KByte) 32768
Total PE 508
Free PE 0
Allocated PE 508
PV UUID AQLigU-Kra3-qXIU-ul0J-flmS-cB5j-RfAaEv
"/dev/xvdb" is a new physical volume of "4.00 GB"
--- NEW Physical volume ---
PV Name /dev/xvdb
VG Name
PV Size 4.00 GB
Allocatable NO
PE Size (KByte) 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID 4sg3Xe-ryzB-6nL1-pyfb-2g9S-e3C3-32bv9m
5. 将新增的PV物理卷/dev/xvdb增加到VG卷组VolGroup00
# vgextend VolGroup00 /dev/xvdb
[root@server1 ~]# vgdisplay
--- Volume group ---
VG Name VolGroup00
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 4
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 19.84 GB
PE Size 32.00 MB
Total PE 635
Alloc PE / Size 508 / 15.88 GB
Free PE / Size 127 / 3.97 GB
VG UUID FbUuvN-yE0U-cRkA-fOL0-aIRP-eHdG-TzDN5P
6. 扩容LV逻辑卷/dev/VolGroup00/LogVol00
[root@server1 ~]# lvextend -l +127 /dev/VolGroup00/LogVol00
Extending logical volume LogVol00 to 17.81 GB
Logical volume LogVol00 successfully resized
[root@server1 ~]# vgdisplay
--- Volume group ---
VG Name VolGroup00
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 5
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 19.84 GB
PE Size 32.00 MB
Total PE 635
Alloc PE / Size 635 / 19.84 GB
Free PE / Size 0 / 0
VG UUID FbUuvN-yE0U-cRkA-fOL0-aIRP-eHdG-TzDN5P
[root@server1 ~]# lvdisplay
--- Logical volume ---
LV Name /dev/VolGroup00/LogVol00
VG Name VolGroup00
LV UUID bLPTMQ-3TlN-1pIO-vKUv-oU9A-mYnh-dLdqFF
LV Write Access read/write
LV Status available
# open 1
LV Size 17.81 GB
Current LE 570
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 YDw1jP-eF7K-Yrms-H0QD-4f7p-oPMv-PeXqrO
LV Write Access read/write
LV Status available
# open 1
LV Size 2.03 GB
Current LE 65
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:1
7. LV扩容后激活变更以扩容文件系统
[root@server1 ~]# df -m
Filesystem 1M-blocks Used Available Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
13732 3086 9938 24% /
/dev/xvda1 99 14 80 15% /boot
tmpfs 256 0 256 0% /dev/shm
[root@server1 ~]# 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 4669440 (4k) blocks.
The filesystem on /dev/VolGroup00/LogVol00 is now 4669440 blocks long.
[root@server1 ~]# df -m
Filesystem 1M-blocks Used Available Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
17668 3090 13669 19% /
/dev/xvda1 99 14 80 15% /boot
tmpfs 256 0 256 0% /dev/shm
8. 至此，为虚拟机扩容根分区成功，扩容容量为127个PE(32M/PE)，扩容大小为4G。