Trouble Getting VMware HA Working? – Basic Troubleshooting For VMware’s HA


Trouble with your HA config? vCenter (VirtualCenter) giving you all kinds of crap while setting it up? Let’s take a look some things to do when ‘Configure HA’ bunks up.

Do you meet the requirements?

There are a few things that you need in order to make sure all the bits of HA work. There aren’t many, but without them, it all just falls apart. What are they?

– Shared Storage.
All HA VM’s and config files MUST reside on shared storage. All Clustered hosts, must have access to said storage.

– Networking.
All Clustered hosts must have access to the same networks.
Clustered hosts “Should” have redundant network paths for Service Console networks
DNS needs to be happy, both hosts should be able to resolve the other by host name.
Have you set up NTP?  Time is also important, so make sure you hosts are within 1 minute of each other and in the same time zone.

Of the requirements, DNS usually bites most folks. DNS needs to work if you are using VI. Period.

OK, so, you’ve met the requirements, but HA is still giving you the finger? There are some basic steps to follow before going too deep. Here they are:

  1. Right click the host, click “Reconfigure for VMware HA”.
  2. Failing that, put the host into maintenance mode, remove from the cluster, exit maintenance mode, and rejoin the cluster.
  3. Reboot the host.

So failing all of the above, we can look in a few places for VMware HA logs to gain better insight. The first is vCenter itself, the second is: /opt/vmware/aam/ on the host in question (or /opt/LGTO… for older vCenter/ESX deployments).

This covered some HA troubleshooting basics. I’ll cover some more specific examples at request.

Source: VMWare Resource Management Guide

Photo by: andreasnilsson1976