For the past few weeks, my customers keep received an alarm “Host connection failure” email alerts via VMware vCenter but end up it’s a false alarm.

The email alert example as below:
Target: kulsrvprd01.malaysiavm.com
Stateless event alarm

Alarm Definition:
([Event alarm expression: Cannot connect host - incorrect Ccagent] OR [Event alarm expression: Cannot connect host - network error] OR [Event alarm expression: Cannot connect host - time-out] OR [Event alarm expression: Cannot connect host - time-out] OR [Event alarm expression: Host connection lost])

Event details:
Host kulsrvprd01.malaysiavm.com in DC1 is not responding

VMware Technical support team was told us this is a known bug in current release vSphere 4.0. The VMware engineering team is still working on it and the fix for this issue will be next released.

Quick Help: You can stop the alarm immediately after make any changes on the alarm definition such as changed the Alarm Action notification setting frequency from 5 minutes to 10 minutes.

Anyway, I would suggest to keep “Host connection failure” alarm enable. And let’s wait for the patches. Hope you’re aware about the problem.

Additional Tips: Learn How to configure Email Alert here.

• First login to Virtual Infrastructure client, go to Administration -> VirtualCenter Management Server Configuration.

• Click on Mail, enter your SMTP server IP address or hostname and sender account.

• By system default, you should able to see some of the alarms definition.

• Right click on one of the defintions, click Actions and key in the email address that you wish to receive email alerts.

Basically, the VMware ESX will send an email notification to the corresponder email address when trigger alarms.

If you looking for additional alarm, right click on ESX hostname on virtual center and click Add Alarm.