Hi All, I have finally made it to the last page of this tutorial! Yay! https://www.howtoforge.com/tutorial...ase-cluster-on-debian-8.4-with-ispconfig-3/5/ Installing on Debian 9. Very similar, not many changes. But one final one is a slight difference as mentioned by a comment from "dmgeurts" at the bottom of the page - the "iterate_query" also has WHERE service_id = '1' at the end of it. Should we leave this in or take it out? I'm also concerned that on server 1 it is id = 1, but on server 2 it is id = 3. Either way, I can't get it to work, the output of this command: doveadm replicator status '*' is this: [email protected]:/# doveadm replicator status '*' username priority fast sync full sync success sync failed [email protected]:/# Doesn't seem to give any error, so I'm not sure where to look. Any ideas? The UFW firewall status is "inactive" so it's probably not a firewall issue. The passwords are the same, the server IPs in the config files are correct. I'm out of ideas!