Since at 2013-04-05 04:29:46 UTC, Zuul no more receives events from Gerrit. It uses a CLI command such as:
ssh -p 29418 email@example.com gerrit stream-events
I did stream-events using both the jenkins-bot user and my own account 'hashar'. While submitting a new patchset or posting a comment: nothing is reported.
The end effect is that no jobs are triggered in Jenkins.
The sshd daemon (Mina) would lost connection on one way connections and hitting some kind of timeout. That affected Zuul which idles with a gerrit stream-events.
Gerrit sshd.idleTimeout got set to 10 days as a workaround https://gerrit.wikimedia.org/r/#/c/58126/
https://gerrit-review.googlesource.com/c/gerrit/+/44472 (79b91bfe) is the Gerrit patch.