This is a great set of instructions by David Maphis on how to resize an LVM volume in Linux. I just used these instructions to expand my linux virtual machine hard drive under vmware fusion. OS was Fedora core 6 using lvm. Vmware I used was VMware fusion for the mac but this applies to any linux system using lvm.
Under my vm settings in VMware fusion I expanded the disk to be larger and then followed these instructions for the linux side of things. Obviously the vm has to be shutdown before you mess with the hd size in vmware but all of the linux steps I did on the live system within Xwindows. LV's are great!
Here are David's instructions. You can skip his intro if you are not using vmware server. I injected some notes which you will find in bold.
URL to original pdf: http://www.google.com/url?sa=t&source=web&ct=res&cd=1&url=http%3A%2F%2Fcommunities.vmware.co
m%2Fservlet%2FJiveServlet%2FpreviewBody%2F4900-102-2-3019%2FResizing%2520LVM%2520Volumes%2520in%2520Linux.pdf%3Bjsessionid%3D9DC6B8A9615CEBD28FE94412BA638CE1&ei=VJcVSsioAZio8gSaxKjHAg&usg=AFQjCNGSDpxwdH7ojtEpCwiGR_Yueod_Kg&sig2=oJ4vPtV31iEBovG4xMFuHw
By David Maphis 4/29/2008
In this example I will changed the size of my root partition without
affecting any data. Since this is a VM, I can extend my vmdk with the
“vmkfstools” command. To do this I will have to shutdown the VM to release
the lock on the file then resize it. Power up when complete.
Once this is done, make a partition that uses the available space you wish to
add to the LVM volume using “parted”. It has an interactive shell, so just
enter “parted” in a shell:
parted
(parted) print
Model: VMware Virtual disk (scsi)
Disk /dev/sda: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Number Start End Size Type File system Flags
1 32.3kB 206MB 206MB primary ext3 boot
2 206MB 8587MB 8382MB primary lvm
So I have from 8588MB to 10.7GB available for a new partition. For this
example I’m only using up to 9588MB. Your numbers will obviously vary.
So now let’s make a partition from the new space:
(parted) mkpart primary 8588 9588
(parted) print
Model: VMware Virtual disk (scsi)
Disk /dev/sda: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Number Start End Size Type File system Flags
1 32.3kB 206MB 206MB primary ext3 boot
2 206MB 8587MB 8382MB primary lvm
3 8587MB 9588MB 1001MB primary
You can now see that we have allocated a total of 1001MB of space to
partition 3 or /dev/sda3.
Next we need to create a Physical Volume (PV) with “pvcreate”. LVM also has
an interactive shell, so type “lvm” in a shell prompt:
lvm
lvm> pvcreate /dev/sda3
Physical volume "/dev/sda3" successfully created
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 VolGroup00 lvm2 a- 7.78G 32.00M
/dev/sda3 lvm2 -- 954.44M 954.44M
BFISK NOTE: I did not see sda3 when I ran the pvs command but I was able to proceed with the directions.Now there is a partition that is about 1GB of space available on PV
/dev/sda3.
Now we need to extend the Volume Group (VG) to include the new PV with the
“vgextend” command:
lvm> vgextend VolGroup00 /dev/sda3
Volume group "VolGroup00" successfully extended
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 VolGroup00 lvm2 a- 7.78G 32.00M
/dev/sda3 VolGroup00 lvm2 a- 928.00M 928.00M
BFISK NOTE: I dont think I saw sda3 here either but continued with directionsBy virtue of the fact that we used the same name as the existing VG, we have
now included this PV in the VG.
Extend the Logical Volume (LV) to include the new space with “lvextend”. To
determine that size of the extents we want to add, we first need to view the
VG:
lvm> vgdisplay VolGroup00
--- 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 8.69 GB
PE Size 32.00 MB
Total PE 278
Alloc PE / Size 248 / 7.75 GB
Free PE / Size 30 / 960.00 MB
VG UUID Ll4Bg4-jIFV-lfut-z4Ae-JTfH-0Hzp-Zf9RjM
Looking at this we can see that the total “Free PE” is 30. We will use this
in the following command:
lvm> lvextend -l+30 /dev/VolGroup00/LogVol00
Extending logical volume LogVol00 to 8.19 GB
Logical volume LogVol00 successfully resized
BFISK NOTE: I am not sure what the +30 is. It's not MB and it's not GB. Maybe %? I dunno, I just issued the command until it told me there was no space left. At that point I used -l+10 untill I ran out and then +1, etc until I had no empty space left. lvm> lvs
LV VG Attr LSize Origin Snap% Move Log Copy%
LogVol00 VolGroup00 -wi-ao 8.19G
LogVol01 VolGroup00 -wi-ao 512.00M
So there you are, you have now extended your LV. Now we have to clue the OS
in what is happening.
We need to expand the file system to make the new space visible to the OS
with resize2fs (Fedora, CentOS) or ext2online (RedHat)
[root@labserver02 dev]# df -h /
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
7.1G 1.3G 5.4G 20% /
[root@labserver02 dev]# resize2fs
resize2fs 1.40.2 (12-Jul-2007)
Usage: resize2fs [-d debug_flags] [-f] [-F] [-p] device [new_size]
[root@labserver02 dev]# resize2fs /dev/VolGroup00/LogVol00
resize2fs 1.40.2 (12-Jul-2007)
Filesystem at /dev/VolGroup00/LogVol00 is mounted on /; on-line resizing
required
old desc_blocks = 1, new_desc_blocks = 1
Performing an on-line resize of /dev/VolGroup00/LogVol00 to 2146304 (4k)
blocks.
The filesystem on /dev/VolGroup00/LogVol00 is now 2146304 blocks long.
[root@labserver02 dev]# df -h /
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
8.0G 1.3G 6.3G 17% /
