Bilal Hashmi wrote a nice article about HA today and in this article he asked a couple of questions. As I think the info is useful for everyone I decided to respond through a blog article instead of by commenting. Let me start by saying that in general HA should never be disabled. The later versions of vSphere have a [...]

I was just reading some of the comments posted today and Marc Sevigny, one of the vSphere HA developers, pointed out something which I did not know. I figured this is probably something that many are not aware of so I copied and pasted his comment: Another thing to check if you experience this error is to see if you have [...]

For those who hadn’t seen it yet, the “vSphere 4.1 HA/DRS Deepdive” is available in the Kindle Lending Library! The Kindle Owners’ Lending Library is a collection of books that Amazon Prime members who own a kindle can borrow once a month, with no due dates. (Yes you will need a Kindle Prime subscription!) If you have a Kindle or are [...]

I noticed this thread on the VMTN communtity which discussed a time-out during a cluster election process. The one thing all scenarios described in the topic is that they upgraded from 4.1 to 5.0 or 5.0 base to a higher patch level. Marc Sevigny posted in the same thread that it is a known issue which the HA team is [...]

I had a question from one of my colleagues last week about Isolation Response and IP Storage. His customer has an ISCSI storage infrastructure and recently implemented a new vSphere environment. When one of the hosts was isolated virtual machines were restarted and users started reporting strange problems. What happened was that the HA Isolation Response was configured to “Leave [...]

I had the question today what happens to a powered off VM when the host they are registered against fails? This customer always has multiple powered off VMs and was afraid their VMs would show up as orphaned. I was pretty confident that the VM would be re-registered against one of the remaining hosts in the cluster, but I validated [...]

I wrote an article about the scenario where all host fail, due to for instance a power outage, and how HA responds to it. I had a question today if this was still valid with vSphere 5.0. I figured it wouldn’t hurt to describe the steps that vSphere 5.0 takes. Power Outage, all hosts down Power on hosts Election process [...]