openstack-ansible rabbitmq installs latest release of erlang which is not supported

[Michael Craft]

Hello,

Some recent changes were implemented to upgrade erlang to newer supported versions, but it looks like a consequence of this global release pin is that it now installs erlang 1.20 which is not supported by rabbitmq.

https://www.rabbitmq.com/install-debian.html

I believe this should be fixed by following the guidance provided by rabbitmq documentation in the above url. Pasting specific section here for specific version pinning.

Erlang Release Series Repositories that provide it
20.x NOT SUPPORTED and will lead to DATA LOSS when upgraded to from an earlier Erlang/OTP release, avoid unless this document is updated to suggest otherwise.
19.x Erlang Solutions, Debian Stretch, Debian Jessie backports, Ubuntu Zesty (17.04)
18.x Erlang Solutions, Ubuntu Yakkety (16.10), Ubuntu Xenial (16.04)
17.x Erlang Solutions, Debian Jessie, Debian Wheezy backports
Erlang Version Pinning

apt package pinning can be used to avoid undesired Erlang upgrades. The following preference file example will pin esl-erlang package to to 19.3.6 and erlang-* packages to 19.3 (assuming package epoch for those packages is 1):

# /etc/apt/preferences.d/erlang
Package: erlang*
Pin: version 1:19.3-1
Pin-Priority: 1000

Package: esl-erlang
Pin: version 1:19.3.6
Pin-Priority: 1000
The above example should be placed into a file under /etc/apt/preferences.d/, e.g. /etc/apt/preferences.d/erlang.

[Craig Sayler (craig-sayler)]

@cloudnull - this was the previous fix on erlang version with rabbitmq. - https://review.openstack.org/#/c/473573/
Tested it did not work...

[Michael Craft (michaelgcraft)]

Addtl data from the rabbitmq team
https://groups.google.com/d/msg/rabbitmq-users/_imbAavBYjY/xWYMyhV-AQAJ

Team RabbitMQ has an update on the state of OTP 20 support.

OTP 20 GA is mostly backwards compatible compared to 20-rc1: I could not reproduce upgrade data loss
with any RabbitMQ version from 3.6.4 (first version to support Erlang 19) through 3.6.10 when upgrading from 19.x
to 20.0 GA.

Our point of view on 20 is still this: if you have existing installations to upgrade, wait for RabbitMQ 3.6.11
and upgrade to OTP 20 after that, or even a few months later. New installations can use 20 from the start
if they choose to.

We'd like to thank the OTP team for listening to our rc1 feedback and implementing a (most) compatible
version of term_to_binary/1 for the final release.

[Jean-Philippe Evrard (jean-philippe-evrard)]

That should be solved now. Could you try again?

[Jean-Philippe Evrard (jean-philippe-evrard)]

(See: https://review.openstack.org/#/c/478548/ and https://review.openstack.org/#/c/478679)

[Michael Craft (michaelgcraft)]

Verified by hand on newton branch. Unable to test integrated patch since our regions are not on ocata yet. thanks!

[Launchpad Janitor (janitor)]

[Expired for openstack-ansible because there has been no activity for 60 days.]