During patching of a vCenter server appliance (VCSA) problems can occur. Maybe contact to the update source was lost or the whole process has been cancelled by an operator. If you try to reapply the patch, you might see an error like in the picture below.
Update Installation failed. VCenter Server is not operational.
In the VAMI interface of vCenter everything looks fine. All services are up and running and ovarall status is green. Even a reboot of the appliance doesn’t help. The source of the problem lies in an interrupted update procedure which leaves a status file behind. We need to fix (remove) that manually.
To do so open a SSH shell to the vCenter server appliance and change to the directory where the file was left.
# cd /etc/applmgmt/appliance
You’ll see a file called software_update_state.conf. Under normal circumstances this file will be removed after an update. But something went wrong and it wasn’t cleaned up. Let’s have a brief look inside the file.
On October 16th 2018 vSphere 6.7 Update 1 became available. An update we’ve been desperately waiting for. Finally vSphere-Client (HTML5) has become fully functional. Until that some tasks had to be done with the infamous flash client.
VMware and Veeam worked hard to identify the root cause of the problem. It turned out that there was a change in the vSphere API which caused communication issues with Veeam Backup.
Latest API version is 6.7.1, but this one seems to be incompatible with Veeam Backup 9.5 U3a. According to Veeam sources, the issue will be settled with the soon to come Veeam Backup Update 4.
For all of those who have already updated their clusters to vSphere 6.7 U1 there’s a workaround. You need to enter a registry key to force Veeam Backup using the older API 6.7.
Warning! This solution is not recommended by Veeam Support. If you’re not yet on vSphere 6.7 U1 and you’re using Veeam Backup, you better wait until release of Veeam Backup 9.5 Update 4. Do not upgrade. Read this passage again!
The workaround outlined below has to be reverted as soon as Veeam 9.5 Update 4 is available.
HKLM\SOFTWARE\Veeam\Veeam Backup and Replication
You need to add a multi-string-value (REG_MULTI_SZ). Enter the Value below:
6.7.1 = 6.7
This registry key forces Veeam Backup to use API 6.7, but might lead to other yet unknown problems. But it enables to run your Veeam Backup jobs again.
Since vSphere 6.5 the HTML5 client (vSphere-Client) is an integral part of the environment and is geting updated with more and more features with every release of vCenter. It is to get rid of the infamous flash client (web-client) sooner or later.
In distributions below 6.5 there’s no HTML5 client included. But it is possible to get the functionality with a fling.