Last week VMware released a patch to fix another issue with Change Block Tracking (CBT) which took the ESXi 6.0 Update 1 Build to 3247720. The update bundle contains a number of updates to the esx-base including the resolution of the CBT issue.
This patch updates the esx-base VIB to resolve an issue that occurs when you run virtual machine backups which utilize Changed Block Tracking (CBT) in ESXi 6.0, the CBT API call QueryDiskChangedAreas() might return incorrect changed sectors that results in inconsistent incremental virtual machine backups. The issue occurs as the CBT fails to track changed blocks on the VMs having I/O during snapshot consolidation.
Having just deployed and configured a new Management Cluster consisting of four ESXI 6.0 Update 1 hosts running VSAN I was keen to get the patch installed so that VDP based backups would work without issue however once I had deployed the update (via esxcli) to the first three hosts I saw that the VSAN Health Checker was raising a warning against the cluster. Digging into the VSAN Health Check Web Client Monitor view I saw the following under HCL Health -> Controller Driver Test
As I posted early November there was an important driver and firmware update that was released by VMware and DELL that resolved a number of critical issues with VSAN when put under load. The driver package is shown above against node-104 as 6.606.12.00-1OEM.600.0.0.2159203 and that shows a Passed Driver Health state. The others are all in the Warning state and the version is 6.605.08.00-7vmw.600.1.17.3029758.
What’s happened here is that the ESXi Patch has “updated” the Controller driver to the latest VMware driver number and has overwritten the driver released on the 19th of May and the one listed on the VMware VSAN HCL Page. The simple fix is to reinstall the OEM drivers so that you are left back with the VSAN Health Status as shown below.
Interestingly the Device now shows up as a Avago (LSI) MegaRAID SAS Invader Controller instead of a FD332-PERC (Dual ROC) … I questioned that with a member of the VSAN team and it looks as though that is indeed the OEM name for the FD332 Percs.
So be aware when updating ESXi builds to ensure the updated drivers haven’t removed/replaced it with anything that’s going to potentially give you a really bad time with VSAN…or any other component for that matter.