Extended VMFS 3 datastore, but can't see new space

[NJKwork]

Hi,

We just added 3 new 37.5 GB extents to a VMFS-3 datastore, but the size is still showing the old value. We have tried rescanning and refreshing - but nothing works.

Under "Extends" I see 4 LUNS (the original plus the 3 new ones) but the "Total Formatted Capicity" still only shows "37.25 GB" which is from the original LUN.

How do I get the 3 new Extends to increase the usable space?

Our Config:

ESX 3.0.1

VirtualCenter 2.0.1

SAN is EMC

Servers are HP DL585 G2 (AMD)

HBA's are QLogic (dual with Multi-pathing enabled)

Farm size is 3 ESX server

VFD shows correct size on 1 of the 3 servers, the other 2 still show the old size. VC shows the old size on all 3 servers.

Thanks

SlickBag

[sbeaver]

You are going to need to add another VMFS partition out of the extended space

[NJKwork]

Hi,

Thanks for taking the time to respond - but I am a bit confused. I thought the purpose of extents was to take an existing VMFS volume and make it bigger. So if I have a datastore called "workstations-v3" which is 35 GB, and I want more space on it (so I can build move VMs on that datastore) I can "grow it" by adding additional extents to it. So our SAN administrator has masked in 3 additional 35 GB LUNS and now I added those extents to my workstations-v3 datastore. However, instead of seeing a 140 GB datastore, I still only see the original 35 GB.

Why would I need to create another VMFS parition? That would not allow me to increase the size of the datastore I already have, would it?

Thanks

Slickbag

[sbeaver]

Did you format the new space VMFS before you added the luns as extents

[NJKwork]

Well - I actually did not do it extending, my co-worked did it....

but according to him, it formats it for you when you extend it. He said with version 2.x you had to format it first, but now with version 3.x, it formats it for you during the extend process (and tells that it is formating too). I am trying to verify this.

Thanks

SlickBag

[NJKwork]

We tried creating a concatenated SAN volume, added space to it, and then added the Extent from the new space on the volume - and that seems to work. But using a new LUN does not.

[Rumple]

I'm sure you know, but adding extents to expand luns is not a best practice and most of us will not recommend doing it at all.

May I also ask why you keep making 35GB LUNS? There was a huge thread a while back in esx 2 about some SAN admin only making 30GB LUN's because that was as big as you should make lun's but in reality that is 10 year old thinking. I have upwards of 700GB LUNS for the File server, but that limit is so we can multithread our backups not a limitation of the SAN.

We make luns for ESX 2.X big enough for 10-12VM's so about 250GB each (in our case its 2-10GB disk files typically). In ESX 3 we are going with alot more then that (I created 2-500GB LUNS to give to the 2ESX Servers)

[wcrahen]

Does ESX see the new LUN under storage? Also, I have seen where a reboot is needed for extents to become visable.

[acr]

Ok so you want to extend a VMFS partition which as you know is only really achieveable by creating another VMFS partition then adding to the existing VMFS partition so it looks as one bigger VMFS partition...!!

(IMHO) Dont.. Just create the second VMFS partition and start using it as a second separate partiton.. Extents are a nice idea, better now than they were, but not really best practice..

[NJKwork]

OK - sort of forgot of this question and just getting back to it now....

1) Our SAN administrator gives us small chunks at a time. I think he is afraid to overcommit space - give too much and you can never get it back if we never use it - which I can understand and appreciate. So he gives us small chunks as we need it. But to be fair, this particular DS was for a small subset of VMs we were working with. Our production servers DS is, as suggested, quite large (400 GB). But even it will eventually run out of space.

2) Reboot is a horrible solution. That means we have to Vmotion 20 guests, reboot, Vmotion 25 guests, reboot, etc. for as many ESX hosts as we have. That SUCKS in my opinion - but maybe others can do it without losing sanity.

3) Adding new datastores kinda sucks too. What if you get down to, say, 1 GB free on a datastore and then need to create some SNAPSHOTs on it for a few guests? Being able to add extents to a DS seems like a reasonable option to help with this. I have read that you can create snapshots on other volumes - but then that screws up our backup scripts which are based on snapshots existing on the same volume as the guests (I didn't design the backup system so I really don't understand the full details).

Anyway - the documentation says you can do it (and they provide the extent functionality in the product regardless of what the documentation says). If not, they should remove it from the docs and remove the extent functions from the tools. Seems like this is a bug, everyone knows it is a bug, labels it as "not best practice" and just works around it instead of VMware being standup guys and fixing the problem.

But I thank all for the advice. To be honest with you, I agree with 95% of what you are saying. Just most of it is out of my control.

SlickBag

[Barbaton]

I just went through the exact same problem. Adding extents briefly (3-5 secs) showed the total new space but then went back to its original value.

I got it to show up properly by putting one of my hosts in Maintenance Mode and migrating all of the machines, rebooting it, and reconnecting it. Now all of them show the proper size.

So it works, sort of. It's not completely dynamic but at least a work around.

[Barbaton]

I just went through the exact same problem. Adding

extents briefly (3-5 secs) showed the total new space

but then went back to its original value.

I got it to show up properly by putting one of my

hosts in Maintenance Mode and migrating all of the

machines, rebooting it, and reconnecting it. Now all

of them show the proper size.

So it works, sort of. It's not completely dynamic but

at least a work around.7

It appears I spoke too soon. After a while it reverts to the original size. I have a call in.

[ekooter]

Hi there,

I see the same problem, this in a cluster.

I increased the size the lun on the SAN, did a rescan, an added an extent to the vmfs. Everythig seemed fine, until the next day, teh new space was gone.

An individual host (new install) connecting to the same vmfs shows the new size, the hosts in the cluster show the old size. All the hosts show the new extent, in configuration, storage. After rescanning on all hosts, it briefly showed the new size on all hosts, only to revert to the old size after 30 minutes....

Also, after adding the new host to the cluster it only shows the old size...

Thanks,

Evert

[RMartilla]

I am having similiar problems which I posted about already. I guess this isn't getting answered since nothing has been posted since February...

[robi1a]

I got the same problem. Adding new extents but VI3 Client shows the old value. One thing you can do is to create a new file in the extended datastore with dd (dd if=/dev/zero of=file ...) to fill up allmost the space. After this VI3 Client shows the true value und you can delete the temp file.

[thecow]

hello,

Me too, same problems after extend:

view in ESX3.0.1 host individually (integrated to VC) =new size

view in Virtual center= old size

view in ESX3.0.0 host individually (not integrated to VC)=old size

thks

[DarkLordSilver]

Hello Mates

Recently, I had the same problems with a ESX cluster at a customer.

I tried all the stuff in this thread, but nothing helped me out.

The extend was visible, but only at the ESX it was created on. All the other host didn't see the filesystem, niether in the GUI or the CLI.

So here is what i did, to solve the Problem.

1. Create extend at server x

2. Make sure the extend is created correctly and displayed in the GUI.

3. Set the host to maintainece mode and reboot it.

4. If the host is back on, you have to reboot every ESX host, where the extend should be visible.

Now the extend never disappears again!

I've done it this way with a 3,9 TB VMFS and it works fine, also with the DMZ VMFS with 900 GB.

and here my closing words:

Never, really never use extends, if you don't have to! I tought that extend would be a very nice feature, but it isn't! I'll be aware of working with extends in the future!

Greetings from frosty switzerland

Stefan