Can primary and backup TServers be different versions?

[ChrisM]

Hi,

This may sound like a strange question, but can a warm standby primary and backup server pair be different versions?  I need to test a new TServer (8.1 vs 7.6), but due to some issues in our pre production environment I have to do it in production.  My thought was to replace the current 7.6 backup with the new 8.1, and use the SCI / warm standby switchover function to run on the 8.1.  We would do this after hours and test, and if it all checks out possibly leave the "backup" 8.1 running in primary mode for a couple of days to continue observing and check our reporting.  If all goes well we could then upgrade the 7.6 primary to 8.1 as well and then have the primary / backup pair on the same release.  Conversely if we have problems I could use the HA switchover feature to quickly switch back to the current 7.6 primary.

However, I'm not sure if this will work or be allowed with the primary and backup temporarily being different versions from each other.

[borkokrz]

Look for the Rolling Upgrades in TServer deployment guides or Release Notes or Genesys Migration Guide. Per example for Alcatel A4400 you need at least 7.2+ for this to work. I'm not sure if SIP Server officially also support this feature. Few times I've done this kind of upgrade, but in case of SIP only in pre-production.

[Tambo]

Our upgrades have been completed one at a time in the live environment with no issues

[Kevin S]

I think all the Genesys documentation recommends that the primary/backup pair be the same major/minor version (7.6/7.6, 8.0/8.0, etc). HOwever, I also have run a primary/backup TServer pair of different versions during upgrades without a negative impact.