Question regarding cluster rolling upgrade

[ollie 32]

Hi team.

I'm planning to upgrade a cluster in production using rolling upgrade. And it seems it is possible to upgrade all the way to the latest version with some intermediate steps. (say, 3.9.x to 3.12.x) Considering RabbitMQ and Erlang compatibility, it is unavoidable to upgrade Erlang version altogether.

Consulting with some relevant manuals, I found the following lines.

https://www.rabbitmq.com/which-erlang.html#clusters

Seems it is recommended against to cluster nodes with different Erlang major versions.

https://www.rabbitmq.com/upgrade.html#rabbitmq-version-upgradability

RabbitMQ documentation says it is possible to rolling upgrade a cluster from 3.7.18 to the latest. (of course with some intermediate steps)

I feel like above two arguments are in conflict in some sense. When doing cluster rolling upgrades, nodes with different Erlang major version would coexist for some period of time.

So the question is, is it safe to rolling upgrade a cluster with Erlang major version change?

Thanks in advance.

[Michal Kuratczyk]

The paragraph you linked to does mention the upgrade exception:

"Outside of a reasonably long upgrade time window, it is recommended that all nodes use exactly the same version of Erlang."

(I guess the wording could be a bit better).

Don't forget to enable all feature flags after each upgrade!

--
You received this message because you are subscribed to the Google Groups "rabbitmq-users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to rabbitmq-user...@googlegroups.com.
To view this discussion on the web, visit https://groups.google.com/d/msgid/rabbitmq-users/1f361574-9961-44b6-8691-8c43436e2a1en%40googlegroups.com.

--

Michał

RabbitMQ team

[ollie 32]

Thanks for the quick reply!!

2023년 8월 17일 목요일 오후 6시 26분 50초 UTC+9에 Michal Kuratczyk님이 작성: