By default, if Postgres is started as a replica, it will download all the WAL it can find from the archive, apply the data changes and promote itself to the primary role. To avoid this and keep the Postgres replica running as a read replica, we need to configure it to run in standby mode. To do so, place a file called`standby.signal` into the data directory, like so:

sudo -u postgres touch /var/lib/postgresql/14/main/standby.signal

Finally, the replica is ready to start:

sudo service postgresql start

If you connect to it with`psql`, you can validate it's running in read-only mode:

SELECT pg_is_in_recovery();