How to increase existing LUN size on EVA3000

[Danesh Qureshi]

I have a EVA3000 SAN which has LUN 2 allocated with 10GB of disk space. The LUN has been presented to a HP Proliant DL740 system which is running Redhat Enterprise Linux AS 3. I wish to increase the partion size from 10GB to 50GB on one of the partitions on the HP DL740 system which has the 10GB of disk space allocated to it by the EVA3000.

I can see the allocated space to LUN 2 when I am using eva command view.

Can I increase the LUN size currently from the allocated size of 10GB to 50GB on the EVA3000 without corrupting the data on the LUN?

If I can increase the LUN size then please can someone show me the steps involved to do it?

[Vincent Fleming · Accepted solution]

Just go to the Vdisk Properties page, change the size from 20 to 50, and click the Save Changes button.

It takes 3-4 seconds to increase the size of the LUN.

It will NOT corrupt your data.

Now, getting your host to recognize that the LUN has changed may be another matter...

RH AS 3 is a little old... Are you using LVM?

[Danesh Qureshi]

Yes I am using LVM to create logical volumes.

I have been doing some reading about LVM on RH AS 3 but it looks like there is no lvm command to increase the physical size of the disk on RH AS 3.
Is that that case?

When I initially created the LUN on the EVA3000 I gave it 10GB size and presented it 10GB to the host. I then used fdisk but only setup 5GB of the 10GB alloacted by the EVA3000.

See below fdisk displays 10GB size for disk /dev/sdb.

fdisk -l /dev/sdb

Disk /dev/sdb: 10.7 GB, 10737418240 bytes
255 heads, 63 sectors/track, 1305 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sdb1 1 653 5245191 83 Linux

See below pvdisplay shows only 5GB allocated to /dev/sdb1

# pvdisplay /dev/sdb1
--- Physical volume ---
PV Name /dev/sdb1
VG Name vg_dba
PV Size 5 GB [10490382 secs] / NOT usable 32.19 MB [LVM: 128 KB]
PV# 1
PV Status NOT available
Allocatable yes (but full)
Cur LV 1
PE Size (KByte) 32768
Total PE 159
Free PE 0
Allocated PE 159
PV UUID ZWttEO-GbCt-Qaux-oGRK-vq7S-E8tq-70A4Mr


Can I extend the physical size from 5GB to 10GB using a lvm command?

[Ivan Ferreira]

Hi, please see this thread:

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1131222

[Ivan Ferreira]

Finally, I had the opportunity to do a real test of growing a LUN. Here are the results.

[Danesh Qureshi]

The results of your testing will be very useful to me for servers which are running on RHEL AS 4 which use LVM2.

However, my server is running RHEL AS 3 which has 10Gb presented by the EVA3000 and I have allocated only 5Gb.Now I wish to utilise the remaining 5Gb of space. How do I use LVM extend from 5Gb to 10Gb?

[Ivan Ferreira]

I need the output of:

vgs
lvs
vgdisplay -v
lvdisplay -v
df

The name of the file system to extend.

Normally, you only need to run lvextend and then resize2fs.

[Danesh Qureshi]

The name of the file system I wish to extend is /dba.

See attached file containing output of the commands you asked me to invoke.

[Ivan Ferreira]

From the output of your commands it's possible to identify that:

- /dev/vg_dba/lv_dba is the logical volume for file system mounted in /dba
- /dev/vg_dba/lv_dba belogs to the vg_dba volume group
- vg_dba volume group has one physical volume in it /dev/sdb1
- vg_dba has 0 Free PE, so you cannot extend the logical volume without adding another disk to the volume group

What you should do is:

- Create a new vdisk in the EVA with the apropiate size and present it to the host.
- Make the host rescan the disk, for example, with hp_rescan -a or rescan_scsi_bus.sh
- A new device will appear, for example, /dev/sdc, in the output of fdisk -l
- You can create a new partition on sdc and set type 8e (fdisk /dev/sdc - n, p, 1, ENTER, ENTER, t, 8e, p, w)
- Prepare the partition to be used with LVM with pvcreate /dev/sdc1
- Extend the volume group with vgextend vg_dba /dev/sdc1
- Extend the logical volume with lvextend -L + /dev/vg_dba/lv_dba
- Extend the file system with resize2fs or ext2online

[Danesh Qureshi]

I was finally able to increase the file system size to 50Gb on the /dba file system.

Thank you