Hi, I was wondering what is the safest pg_upgrade version upgrade distance going from 9.6 version. Do I need to go version by version or I can go from 9.6 to 15? We have a very huge database(TBs) with one replication server, so we will first run the pgupgrade on the main server and then rsync to a standby replica. I'm not sure whether it's safe to do it from 9.6 to 15 at once, I have tested the process on 9,6 to 10 yet. Would that be a wise approach to such an upgrade of the db?
Also, when upgrading a very big database with replication where none of the data can be allowed to be lost, is the pgupgrade into rsync approach the best one? Thanks.