VMWARE How do I diagnose a disk latency issue?

[chazzy2501]

I'm on Vmware esxi5.1 using vsphere. I'm getting the event log that device (naa.600xxx) i/o latency has an increaded average. The device in question is the SATA storage on my SAN.

 

The setup is that my fast lun (lun0) is on my 15K SAS drives and that is where all the VM operating systems (c: drives) live and the exchange database. The SATA storage (lun1&2)is where I keep the VMs data (file shares).

 

The SATA storage is divided into 2 luns and is used by 6 servers. How should I diagnose what VM is causing the issue? I cant find a corrolation between scheduled tasks or daily usage. The performance logs show disk activity but as a whole not by lun.

 

How do I diagnose?

[pantscat]

You should be able to look at the historical performance data in the vSphere client for each VM and narrow it down that way - look at the disk performance and see where the highest latency is.