Manual vCNS / vShield Edge HA Little Gem!

Recently, I have been doing lots with vCNS and manual creation / manipulation of vShield Edge devices (posts coming soon). One thing that drive me crazy is a tiny little thing that prompted me to write this quick Little Gem - 'Edge HA' sat on my to do list, and gloated at me..... When creating a manual vShield Edge device in vCNS, there is the usual opportunity to create an pair of appliances for running the pair in High Availability mode. Trouble is, the options for deployment are limited and not very clear. (This might be clear / obvious to some, but weren't to me!) When creating an HA pair, in the vShield Manager console editing the Edge device in question under Settings - the HA Configuration gives few options. Essentially, … [Read more...]

HA Failover Errors in vSphere

In a production system running vSphere 5.1, I've noticed that on occasion an error appears at cluster level about 'HA initiating virtual machine failover'. Checking the host and vCenter logs shows no host reboots or isolation. In this case, there fortunately is a simple fix that seems to rid the cluster of theĀ erroneousĀ error message. Disable HA on the cluster (Right-click cluster > Edit Settings > Uncheck HA checkbox). The hosts will automatically disable HA as part of the cluster settings with no effect to the running VMs on the host. Re-enable HA on the cluster (reverse the settings above). The HA cluster will have an election and elect a new HA master and configure the remainder of the hosts as slaves. Voila! The … [Read more...]

Finding HA Primary Nodes

A question came up in yesterday's "Chad's Choice" webcast about choosing which hosts in a cluster would be configured as HA primary nodes. I'm not going to go into any great detail here about what HA primary nodes are because there is a more comprehensive article on HA freely available over on the Yellow Bricks blog of Duncan Epping. The short answer to whether or not you can choose HA primary nodes is a simple "no". It's not possible. Things are rarely simple though. Technically it is possible (again see Duncan's HA deepdive page for details) but, and this is important, manually choosing HA primaries is not supported - even experimentally. The good news though for anyone who wants to know which hosts are their HA primaries is that … [Read more...]

HA Agent on ESX-HOST in cluster CLUSTER-NAME has an error

If I wanted to, this could be a very big post all about configuring HA correctly. But I don't want to reinvent the wheel. Instead I just want to share my experiences with this error: HA Agent on ESX-HOST in cluster CLUSTER-NAME has an error Odds are that you will eventually see this one pop up in vCenter for one of your ESX 3.x hosts. If you're not sure what it means, well the translation basically is that the host displaying the error could fail and your VMs running on it probably won't get started up automatically on another host. Essentially HA is broken on the host. … [Read more...]