Under what circumstances will we hit this issue?

This workaround only applies if we install a latest OSSPACK and when we try to rollback or install an older dated VOS/Director image. (Any image Pre-Feb 2023). 

A point to note is that this only applies if there is an event of a rollback failure or if you plan to rollback a director or VOS to an older release. [Pre Feb 2023].

What is the workaround and how do we fix this?

The workaround is to run this binary file, which fixes the py2 dependency packages.

You can download the script “fix-python-dependency.bin” from this Support KB or use this Versa download link shared below.

https://upload.versa-networks.com/index.php/s/Pn2fgk9yeefiK9m

1) Copy the script to the node under /tmp directory

2) sudo chmod+x fix-python-dependency.bin

3) sudo ./fix-python-dependency.bin

4) Now try to do a rollback or install the older VOS/Director image. [Pre Feb 2023].

Is there any mitigation plan for the backend compatibility?

Fix and support/ability to auto rollback will be included from Images build on or after March 3rd for 21.2 and 22.1.

Bug-ID: 95237

Description: Downgrade/Rollback ability when the latest OSSpack is used and there is a need to rollback to a image build prior to Feb 2023.

Fix-Release: 21.2.3 or 22.1.3 build on or after, March 5th-2024.