Adding large storage volume to ESX server

[radman]

I have a 5TB local disk array (RAID) that I'm adding to my ESX server (3.5u5).

When I use VirtualCenter (2.5u4) to attempt to add the storage, it shows it correctly at 5TB but only says 1TB is "Available", even though it's a new, empty volume.

I'm not going to have to carve up my JBOD into multiple 1TB volumes, am I? That would eat up a lot of disks as hot spares since I'd have to have some for each volume...

FWIW this is a Sun x4150 server, with a J4500 external JBOD array with 44 256GB disks configured as a single RAID 10 volume (and 3 hot spares), using a Sun StorageTek 8-port RAID External controller.

Thanks,

Bob

[Troy_Clavell · Accepted solution]

The maximum LUN size you can present is 2TB.

http://www.vmware.com/pdf/vi3_35/esx_3/r35u2/vi3_35_25_u2_config_max.pdf

[vmroyale]

Hello.

There is also some information on this in kb 3371739.

Good Luck!

[radman]

Thanks. Can you explain why I'm only seeing 1TB "Available"?

I'd hate to go to all the trouble to reconfigure to 3 logical volumes (2 x 2TB + 1 x 1TB, with spares for each) only to find that I still only see 1TB on each...

[Troy_Clavell]

usually ESX will see in the large volume, anything less that does not equal the 2TB -512byte limit. Is the volume you are presenting 5TB?, nothing more?

but as you mentioned you will have to carve up smaller volumes. I don't like the idea of presenting the maximum size LUN to an ESX Host. I typically ask my storage guys to give me 500 or 600GB chunks.

[radman]

usually ESX will see in the large volume, anything less that does not equal the 2TB -512byte limit. Is the volume you are presenting 5TB?, nothing more?

It's somewhere between 5-6 TB.

but as you mentioned you will have to carve up smaller volumes. I don't like the idea of presenting the maximum size LUN to an ESX Host. I typically ask my storage guys to give me 500 or 600GB chunks.

I inherited the array and have nothing else to use it for, so thought I'd just present the whole thing.

Why don't you like approaching the max size LUN?

-Bob

[Troy_Clavell]

>

Why don't you like approaching the max size LUN?

more disk typically means more vm's, which typically means more disk I/0, which could result in performance problems.

just my opinion though. You can use the maximum if you'd like, but you will see most people using LUNs around 500 - 600GB.

[willymaykett]

Just my 2 cents worth, I had a similiar experience with a 3TB disk, turned out I could only see 1TB. When added an extra 500GB, I could then see 1.5TB. My reasoning is that it only sees what is left AFTER the 2 TB limit was reached, and not the first full 2TB of the 3.5 TB.

It may be the same for you....