After switching to phab1001 from iridium, two problems remain which we (@Dzahn and myself) have been unable to figure out.
- IPv6 connections to/from phab1001 don't work. This caused phab to be unable to send mail for a while because it was connecting to mx1001 via ipv6. This is temporarily worked around by hard-coding the IPv4 address for mx1001 and mx2001 in phabricator's config.
- git-ssh.wikimedia.org refuses connections. The service is up on phab1001 and it's listening on the right IPs/port 22. pybal complained initially but we resolved that by depooling/repooling the node.
git-ssh.wikimedia.org might be unrelated to the ipv6 problem but I suspect they are the same root cause?
I think we need help from netops on this one.