Puppet was stuck on this machine.
It's now unstuck as well.

Yes, we did, thanks for triaging ;)

I believe @ardumont or @vsellier fixed this at some point...

Rebase to latest production branch

I confirm that using the fix published in our mirror and proposed upstream, it now works!

There is an issue in the pgbouncer puppet module [1]
I'm fixing it [2], checking it works [3]
I opened the issue upstream.
I also opened a PR to fix it upstream [4]

Branch diff to production branch

Remove dest_db as the source and destination names are the same

As mentioned:

• add the missing destination db cluster port (that would have been a source of connection failures)
• explicit all actual existing pgbouncer options (this diff now gives the same output as grep -v '^;' /etc/pgbouncer/pgbouncer.ini)