On Thu, 2021-04-22 at 10:16 +0700, Victor Sudakov wrote: > After a streaming standby has been down for a time, I know of two > options for it to catch up with the master: > > 1. The replica can fetch all the necessary WAL records via the > replication protocol from the master (unless max_slot_wal_keep_size is > not the default -1, all the required WAL archives should be available from > the master). > > 2. The replica can be provided with a restore_command and will fetch > all WAL files from the WAL archive before starting streaming WAL from > the master. > > Which is the preferred way? > > Of course if max_slot_wal_keep_size is limited, the second options seems > the only safe one. > > OTOH, if the master does not write to a WAL archive, only the first > option is left to us. Both methods are equally feasible. Which one you choose depends on your situation, just as you describe in the last two sentences. Yours, Laurenz Albe -- Cybertec | https://www.cybertec-postgresql.com
