Hi All,
ESXi Host version - VMware ESXi 5.1.0 build-1612806
We use EMC VNX FC SAN for our prod. cluster and we observer SAN CPU hike goes up to 75% during 4.15 AM - 4.45 AM ONLY. We are more concern about Write I/O high. Rest of the time it's quite normal. This happens irrespective of Operating systems. We have done the followings to understand this further,
1) Our SAN admin raised a case with EMC to find out any issue from SAN side. Outcome: No issues in SAN
2) I raised a case with VMware to find out whats going on. Outcome: No issues in visualization layer.
3) Checked the backup window and found that this is not backup window.
4) Monitored the VM's performance using vSphere client. It is evident that there is high Disk utilization and high disk latency.
I am going to perform the followings,
1) Run perfmon on Widows machines
2) Run ESXTOP during that time to get some idea.
Please let me know your thoughts on this. Have you come across this in your environment? Your help greatly appreciated.
