I recently installed 2 new vSphere 5.1 hosts and deployed a new instance of vCenter 5.1 in our lab environment. Inevitably shortly thereafter VMware released version 5.1a to address some upgrade issues and to support View 5.1 on top of vSphere 5.1. KB article on this upgrade here.

From VMware Update Manager I was able to quickly and with minimal effort remediate both new vSphere 5.1 hosts to 5.1a. Then on the vCenter Server…after downloading the new release I updated products in this order:

• Single Sign On
• Inventory Service
• vCenter Server
• Web Client

Everything except the vCenter upgrade went without issue. The vCenter Server upgrade failed during the upgrade of the Profile Driven Storage component. What appears to have happened is during a reboot of the vCenter server the Profile Driven Storage service failed to start because the vCenter Server service was not yet fully started. What happened next was unexpected, when I went looking for the Profile Driven Storage components (after the failed upgrade) in the filesystem it was gone…additionally the service was missing too. I then went to add/remove programs, did a repair of the 5.1 install (using the 5.1 media), the Profile Driven Storage service and files were back and the service was started. I then attempted an upgrade of the vCenter Server to 5.1a and it succeeded. Strange behavior, hope that helps someone.

UPDATE: great post I couldn’t find when I was writing this http://technodrone.blogspot.com/2012/10/going-over-vsphere-510a-release-notes.html