Showing posts from April, 2015

Validating HA by Inducing a PSOD

After installing an ESXi cluster, of course you want to validate its functionality.  vMotion/DRS are easy to validate, but how about HA?  Just pull the power cable out of the back of one of your ESXi hosts, right?

Well, that will do it... but it's also a bit risky.  I've seen host configurations fail to come back from an unexpected power failure and I've heard stories of hardware damage stemming from such an event.  So, a power failure is probably not the best option... so what else can you try?

You could always induce a Host Isolation event.  Simply disconnect all of the network cables from the ESXi host, which will trigger the specified HA response.  That works, but it's a bit of a pain, as you're likely going to need to unplug several cables and keep track of exactly where they belong.  If you're remote, you'll need to involve the network team to get them to shut down specific ports (and you'd better hope that there's no miscommunication regardin…

Clone a Standard vSwitch from one ESXi Host to Another

One of my customers is standardizing the configurations on their HP C7000 enclosures (they've been set up at various sites by various administrators with varying involvement from the architecture team).  As such, we need to stand up some temporary resources so that we can take down the main enclosure for reconfiguration.  That's fine, we can easily ship a smaller enclosure to each site for temporary compute resources.  Some of the sites are using Standard vSwitches, so we need to be able to quickly copy the networking configuration over from their existing blades to these new, slightly different blades.  As I see it, we had 2 good options:

1) Capture a Host Profile with the desired vSwitch configuration.  Delete every other component of the Host Profile so that only the networking section is applied; design the new ESXi hosts so that the vSwitches'll work with the old vmnic-to-vswitch configurations.

2) Write a script to clone the vSwitch from ones ESXi host to another.