Utilising multi-version clustering is the same as doing a full connectivity upgrade and not a zero-downtime upgrade? The only difference is that mvc has replaced cpha cu making it even easier and more seamless compared to before.
I would always go with full connectivity upgrade over a zero-downtime upgrade. It's basically you typing cphacu start as one additional step and it ensures that you will have all the traffic synchronised before doing the failover.
https://sc1.checkpoint.com/documents/R80.30/WebAdminGuides/EN/CP_R80.30_Installation_and_Upgrade_Gui...
But this information is out-of-date. On R80.40+ this is known as multi-version clustering on R80.40+ and has replaced full connectivity upgrade entirely. But it achieves the same thing and is the recommended approach. It has just been made smart, easier and more seamless.
https://sc1.checkpoint.com/documents/R80.40/WebAdminGuides/EN/CP_R80.40_Installation_and_Upgrade_Gui...
Can't really think of any reason why someone would go with zero downtime upgrade over multi-version clustering upgrade / full connectivity upgrade, to be honest.
@chvgms You have to remember that R80.40 comes with 3.10 kernel and a new XFS filesystem. For you to get the new filesystem you will have to do a full re-install for ISO/USB instead of doing a cpuse or blink upgrade. If you do the upgrade you will be stuck with EXT3 filesystem. A full re-install is the only way to get it. A good thing to keep in mind.
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