Hi,
As part of the upgrade path to Zuul v5, which will feature a fully
distributed system (including schedulers), we need to make some
incompatible changes. You can continue to continuously deploy Zuul (we
will in OpenDev), but only if you have already made the required
changes.
As a reminder, here is the overall plan for v4/v5:
http://lists.zuul-ci.org/pipermail/zuul-discuss/2020-March/001158.html
And here are the required changes:
* TLS ZooKeeper connections [1]
* Network connectivity from all components to ZooKeeper
* A SQL database [2]
They are described in more detail in the release notes:
https://zuul-ci.org/docs/zuul/reference/releasenotes.html#relnotes-3-19-0
Starting immediately we will begin merging the changes to implement this
process. That means that if you are continuously deploying Zuul, you
must either have these changes in place as of now, or pin your
installation to a 3.x release while you make those changes.
I encourage everyone to do this ASAP, so that you can continue to
closely track Zuul development. The path from v3 to v5 is intended to
be smooth and one that we can all incrementally follow. They key to
this is not falling behind at the beginning.
-Jim
[1] https://zuul-ci.org/docs/zuul/howtos/zookeeper.html#zk-encrypted-connections
[2] https://zuul-ci.org/docs/zuul/reference/drivers/sql.html#sql-driver