Challenge
If the machine where Veeam Backup & Replication is installed is running Windows Server 2012R2 OS or earlier, and the Nutanix AHV Clusters are running AOS versions 5.20.4+ (LTS) or 6.1.1+ (STS), the following may occur:
Nutanix Clusters that were previously added to Veeam Backup & Replication may become listed as unavailable.
Attempting to add a new cluster may fail with the error:
Failed to get certificate from cluster '<IP>”.
Cause
Starting with AOS versions 5.20.4+ (LTS) or 6.1.1+ (STS), the CBC-based ciphers that Server 2012R2 and older use for TLS1.2 communication are no longer supported, and the ciphers that AOS does support do not exist in the older Windows versions.
Refer to this Nutanix KB article for more information:
https://portal.nutanix.com/page/documents/kbs/details?targetId=kA07V000000LZCuSAO
Solution
Solution 1: Upgrade the Windows OS
Upgrade the server that Veeam Backup & Replication is installed on to Windows Server 2016 or newer.
Solution 2: Modify AOS to Enable the Dropped Ciphers
Enable TLS 1.2 in the Windows OS where Veeam Backup & Replication is installed, and then refer to Nutanix Article for instructions on enabling the dropped ciphers in AOS.
