I have a question about LUN size. I am getting ready to have a vendor setup a HP Storage Works Modular Smart Array P2000 with 20 LFF 450 GB drives. I’m trying to figure out the best way to configure the LUNs to maximize the available space. Can I go with 2 LUNs of 10 disks each which would put each LUN at 3771 GB each? I am going with ESXi 5, all the guests will be Win 2008 R2 64 bit and I plan on having two servers with about 1 TB of desk space and roughly 15-20 servers with 150 GB of disk space.
The max. LUN size for VMFS datastores and physical raw devices in ESXi 5 is ~64TB.
You may configure the MSA with the LUN sizes you mentioned. However, it also depends on the workload of the VMs and whether you do a backup with snapshots. I would probably go with 3 or 4 LUNs and present them on the different controllers.
I'm not familiar with the MSA, however you should be able to create a large RAID set with multiple disk and cut the LUNs out of this RAID set instead of setting up multiple RAID sets with less disks.
André
Hello
This can helpful http://www.yellow-bricks.com/2009/06/23/vmfslun-size/
http://kb.vmware.com/kb/1003565
Please, don't forget the awarding points for "helpful" and/or "correct" answers.
Mauro Bonder - Moderator
It's a good post but it does not answer my question which is, what is the size limit of a LUN with ESXi5.
The max. LUN size for VMFS datastores and physical raw devices in ESXi 5 is ~64TB.
You may configure the MSA with the LUN sizes you mentioned. However, it also depends on the workload of the VMs and whether you do a backup with snapshots. I would probably go with 3 or 4 LUNs and present them on the different controllers.
I'm not familiar with the MSA, however you should be able to create a large RAID set with multiple disk and cut the LUNs out of this RAID set instead of setting up multiple RAID sets with less disks.
André
Look too Maximums of vSphere 5.0 http://www.vmware.com/pdf/vsphere5/r50/vsphere-50-configuration-maximums.pdf
To elaborate on what Andre said before you are also looking at a 2TB limit without the use of extents for a VMFS volume. 64 TB is with the use of up to 32 extents. In my opinion unless you have the need for a single virtual disk greater then 2 TB then size below this. I'm not familiar with your particular storage array but with 20 disks you should be able to size out some smaller sized LUNs as RAID 10 and larger LUNs as Raid 5. This will give you the best balance of performance where needed and capacity as well.