On Mon, Oct 30, 2023 at 6:57 AM Alexander Kukushkin <cyberdemn@xxxxxxxxx> wrote: ... > As Michael already said, the following workflow works just fine (I did it dozens of times): > 1. enable checksums on the standby node > 2. start the standby and let it catch up with the primary > 3. switchover to a standby node > 4. enable checksums on the former primary (now replica). There is also a good trick described in https://www.crunchydata.com/blog/fun-with-pg_checksums to avoid accidental start of Postgres: after pg_ctl stop and before pg_checksums --enable, do: mv data/pg_twophase data/pg_twophase.DO_NOT_START_THIS_DATABASE and once pg_checksums --enable is done, move it back. Additionally, I compiled some thoughts about running pg_checksums without downtime (Patroni-friendly, of course) here: https://twitter.com/samokhvalov/status/1719961485160689993.
