Hi Bron, 3.4 is in RC state now. Were the changes you mentioned (the mailbox tombstone records) necessary for master-master replication already in place?
If not, do you have an ETA? I was planning to deploy a replicated setup at one organisation, but the failover documentation is absent and from your explanation it looks like as a purely manual process. Thanks, Anatoli On 8/4/20 00:53, Bron Gondwana wrote: > > > On Sun, Apr 5, 2020, at 00:45, Olaf Frączyk wrote: >> Hello, >> >> 1. Is currently master-master replication possible (maybe 3.2) Is it OK >> to sync them two-way? > > No, not really. It'll mostly be fine, but it doesn't (yet) handle folder > create/rename/delete safely. > >> If yes - how to set up such config? >> >> 2. If master-master is impossible, is there any guide how to setup >> failover from master to slave and possibly back? If split-brain happens >> - is there an easy recovery from such state? > > The way we do it at Fastmail is with an nginx proxy in front which knows > which one is the master. For a clean shutdown, we shut down the master, then > run sync_client -r -f with the log file (if anything was unreplicated) to > make sure it's up to date, then shut down both and bring them up with the > config pointing the replication the other way. > > For a case where the master crashed hard, we switch the replica to be master > by changing the config (with a restart again) then bring the old master back > up and for sync_client everything again like above to switch back, so all new > changes from the regular replica are back on the regular master. Then we > bring up the regular master as master again, and run sync_client -A from > there to replicate all remaining changes. That mostly works. > > The plan in 3.4+ is to use the mailbox tombstone records to get the > create/rename/delete to the same level of split-brain safety as the UIDs > inside the mailbox have. > > Cheers, > > Bron. > -- > Bron Gondwana > [email protected] > > > > ---- > Cyrus Home Page: http://www.cyrusimap.org/ > List Archives/Info: http://lists.andrew.cmu.edu/pipermail/info-cyrus/ > To Unsubscribe: > https://lists.andrew.cmu.edu/mailman/listinfo/info-cyrus > ------------------------------------------ Cyrus: Info Permalink: https://cyrus.topicbox.com/groups/info/T55e496aba1836d55-Md582355a13df79a2b6c89655 Delivery options: https://cyrus.topicbox.com/groups/info/subscription
