[LUDOC-446] Lustre server rolling upgrades

• Type: Question/Request
• Resolution: Unresolved
• Priority: Minor
• Labels: llnl
• Assignee: Olaf Faaland
• Reporter: Olaf Faaland

Description

The lustre operations manual currently says this:

Lustre software release 2.x.y release (minor) upgrade:
•   All servers must be upgraded at the same time, while some or all clients may be upgraded.
•   Rolling upgrades are supported for minor releases allowing individual servers and clients to be upgraded
without stopping the Lustre file system.

The first sentence sounds like another way of saying "all the servers must be the same". The second sentence sounds like another way of saying "the servers can be different versions, but only temporarily".

As long as:

• "2.x" part of the version is staying the same
• "y" part is changing to "y+1" or "y+2"
• assuming an actual tagged releases

Can we update update the targets within a single file system one at a time? If so, I'll propose a patch with what I think is better wording.