In order to ascertain root cause of IO control issues always good to get digging into the logs, by default not enabled so will need to carry out the following steps – applicable to esxi 5.x/6.x
To enable SIOC logging from the vSphere client:
- Logon to your vSphere client.
- Click on Host | Configuration tab.
- From the left-hand side column named Software, then Advanced Settings. The Advanced Settings pop-up will appear.
- In the parameters list, go down to the Misc section and select the Misc.SIOControlLogLevel parameter.
- By default, it is set to zero, which means it is disabled. To log everything, set the value to
7in the field and click OK to close the pop-up box.
- You will now be able to see the logs in