What is the diffrent in LSI and SCSI disk types ?

singh_padam123 · ‎10-09-2009

Hi,

Is anyone got a chance to get the diffrence and best practice on disk types used in VMware. LSI, SCSI etc.

During P2V which disk type is assigned to the Host. Is the same disk type is assigned during P2V of non-Microsoft as well ?

Plese share your valueble updates and experiences on the same.

AndreTheGiant · ‎10-10-2009

In ESX 3.x there are two virtual SCSI adapter: LSI Logic and Buslogic.

Why two? Cause some guest OS has by default one controller (Buslogic on old Windows OS) or another (LSI Logic for new Windows OS).

Usually LSI Logic could be the right choice.

Andre

Andrew | http://about.me/amauro | http://vinfrastructure.it/ | @Andrea_Mauro

singh_padam123 · ‎10-14-2009

Hi Andre,

Thanks for the update but I am looking for more detailed update on the same. Like performance and OS partaining to disk type. Anyone please..??

chukarma · ‎10-14-2009

Usually LSI is for older OS but in vm cases, it's best to set it as BusLogic. We have experienced SCSI error with VM running LSI driver. Once we switched to Bus, the errors went away and performance increased dramaticly.

Here's a handy white paper from vmware.

http://www.vmware.com/pdf/ESX2_Storage_Performance.pdf

Scissor · ‎10-19-2009

Usually LSI is for older OS but in vm cases, it's best to set it as BusLogic. We have experienced SCSI error with VM running LSI driver. Once we switched to Bus, the errors went away and performance increased dramaticly.

I heard it was the other way -- the virtual LSI SCSI adapter is the newer one. I also found these KB articles pointing out possible performance issues with Buslogic:

- -http://kb.vmware.com/kb/1614

- -http://kb.vmware.com/kb/1890

However, there is this documented problem with newer versions of the LSILogic driver:

- -http://kb.vmware.com/kb/1006224 (so maybe stick with an older driver version?)

And here is some LSILogic tuning knobs to play with that I haven't made time to test yet:

- -http://kb.vmware.com/kb/9645697

I also read that the LSILogic adapter is recommended if you want to set up a Windows 2003 Microsoft Cluster:

- -http://www.vmware.com/pdf/vi3_301_201_mscs.pdf ( page 16 )

All I know for sure is that there is a lot of conflicting information out there, so I guess we all just have to test things ourselves!

AndreTheGiant · ‎10-31-2009