On Sat, Feb 13, 2021 at 10:02:20AM -0600, tsuraan wrote: > I have several streaming replication pairs running under postgres 10, > and I'm looking at upgrading them to postgres 13. Doing that on the > active side is pretty quick and easy: just run pg_upgrade once for > each of versions 11, 12, and 13, then start things up again. That's > tested (on non-replicated instances) and seems to be working great. > The standby side looks a little bit more interesting, so I wanted some > feedback about whether my approach looks safe. > > It looks like the most correct approach would be to discard the > standby systems and just do a new pg_basebackup, but quite a few of > the pairs have a standby on AWS and limited upstream bandwidth, so the > basebackup can take several days. I'd like to avoid that if I can. > > So, my thought is to just upgrade the active side as normal, and once > that's done and the master is back in use, stop the standby's > postgres, call "pg_start_backup(...)" on the master, rsync the changed > files from the running master's data dir to the standby's 10.x data > directory, call "pg_stop_backup()", migrate the recovery.conf into a > postgresql.auto.conf, touch the standby.signal file, and then start > the new postgres 13 on the standby. That seems to work, but I want to > be sure I'm not just having good luck due to the relatively low > activity on my test systems. > > I use named replication slots with my streaming replication, so I > think that the rsync'd pg_wal directory should have everything I need > (or maybe this isn't guaranteed?), and the pg_start/stop_backup will > ensure that all the damage done by rsync'ing an active database can be > repaired from the pg_wal files that rsync fetches. Are those > assumptions right, or am I missing anything else? Is this idea > workable at all? Did you see the pg_upgrade instructions on upgrading standby servers? Why are you not using that? -- Bruce Momjian <bruce@xxxxxxxxxx> https://momjian.us EDB https://enterprisedb.com The usefulness of a cup is in its emptiness, Bruce Lee
