Hold off on ESXi 5.5 Update 3 for now!

Posted By Jon on Oct 1, 2015 | 0 comments

VMware released ESXi 5.5 Update 3 on September 16, 2015.  I was excited to see that VMware released another update for vSphere 5.5 since they are developing 6.0 at a good pace.  I was tempted to deploy it in a lab and check it out but figured I’d wait for other reports on the overall stability of the release.  We run vSphere 5.5 Update 2b on the majority of our client environments so naturally Update 3 peaked my interest.  There aren’t many huge features added in Update 3 – just certification on the PVSCSI controller, log rotation settings, and many bug fixes.  One of the resolved issues I am interested in is an issue regarding monitoring hosts with Dell OpenManage and errors that may be generated.  It’s a delicate situation, though, because there have been some remote code execution bugs and other vulnerabilities identified in pre-Update 3 releases yet Update 3 suffers from a critical bug.

However, as of today (October 1, 2015), VMware released an official entry on their Support Insider blog describing a severe bug.  Apparently, when consolidating snapshots using ESXi 5.5 Update 3 customers may experience VMs failing with an error reading “Unexpected Signal: 11”.  The blog post refers to KB 2133118 but unfortunately the KB does not have a resolution yet.  The resolution steps involve reverting any hosts that have been upgraded back to a former version of ESXi 5.5 and or creating DRS rules to keep VMs from migrating to hosts running ESXi 5.5 Update 3.  That doesn’t sound good!  So, fortunately, I’ve not rolled this update out into the wild yet.

It’s always good practice to let lab and test environments prove significant releases before you deploy to a production environment and this is why.  I am sure VMware will work diligently to resolve the issue and release a subsequent Update 3 revision, but for now stay away from it until they get this sorted out!

Thanks for reading!