Extend or dont Extend a VMFS?

[tropix]

Hi all,

its a good pratice extend VMFS??

I began with two VMFS (vmfs01_storage and vmfs02_storage) of 100Gb.

When I need more space on VMFS, I create another LUN and extend the VMFS.

I'm now about 400Gb in both VMFS. I grow both VMFS extending 100Gb by time.

Could I have a issue with this pratice? Or its better create another VMFS?

Regards,

Eduardo

[esiebert7625]

It's generally not a good practice to extend a VMFS volume. It's better to migrate your VM's to another volume and create a new VMFS volume then migrate them back.

http://www.vmware.com/community/thread.jspa?messageID=61679

http://www.vmware.com/community/thread.jspa?messageID=323671񏁗

http://www.vmware.com/community/thread.jspa?messageID=604008&#604008

fyi...if you find this post helpful, please award points using the Helpful/Correct buttons....thanks

[davidbarclay]

Agreed.

I won't use extents unless I am backed into a corner. Even then I will do it kicking and screaming with disclaimers

Dave

[tropix]

So I have to create another VMFS volumes with 400Gb, and migrate all vmdk to new volumes?

Regards,

Eduardo

[admin · Accepted solution]

Yes, power off the VM and do a cold migrate using VC if you have it, otherwise it's vmkfstools time.

[kix1979]

Yup, but extents are another level of trouble best to avoid. It's a pain to migrate, but by far much less risk in the long run.

[sbeaver]

I also do not do extents except when there is no other choice. Now in ESX 2.x I just did not do them but in 3.0 I have 1 extent currently and although I was not happy about doing this I will say that it has been working well and also handled the SDRF replication test at our DR site perfectly also. So it is better in 3.x but try to avoid if you can

[kix1979]

In VI3 if you lose an extent you only lose the data on that volume, but since you cannot control where the files are placed it can be impossible to predict what will die.

[sbeaver]

Agreed and like I said it is just better in 3.x not anywhere near perfect just better then 2.x

[davidbarclay]

You're not 100% correct Kix, there is one guy who can predict what will die - Murphy!

Dave

[esiebert7625]

Also Father Time, everything eventually fails over time...MTBF

[kix1979]

Lol, thanks for the laugh