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I have patroni/postgresql cluster. when I rebooted leader node in patroni cluster, It has timeline differences after boot

pg_rewind command needs wal_log_hints parameter and so I have configured wal_log_hints=on parameter on cluster-wide. Then tested again with reboot

But pg_rewind command still complains about wal_log_hints

$pg_rewind --target-pgdata=/var/lib/postgresql/14/main --source-server="host=10.0.20.241 port=5433 user=postgres"
pg_rewind: fatal: target server needs to use either data checksums or "wal_log_hints = on"

So when I check this paramter on leader node I mean 10.0.20.241, it is already configured as on postgres@pat02:~

$ psql -p 5433 -U postgres -h localhost -c "select name, setting, applied, error from pg_file_settings where name like 'wal_log%';"
     name      | setting | applied | error 
---------------+---------+---------+-------
 wal_log_hints | on      | t       | 
(1 row)

So how can I use pg_rewind ? To recover timeline issue with patroni reinit command is painfull

Thanks

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    wal_log_hints should have been enabled in the past. At least before the last checkpoint before the point of divergence.
    – Melkij
    Mar 29, 2022 at 12:13
  • @Melkij I configured wal_log_hints in the past. So I restarted all 3 nodes to apply wal_log_hints configuration and then tested Before the test there is no timeline issue, after test (rebooted leader node) timeline issue occured again Mar 29, 2022 at 13:55
  • If pg_rewind complains, you did not have wal_log_hints enabled from the time where the instances diverged. Mar 29, 2022 at 14:32
  • Hello @LaurenzAlbe I did not understand you clearly. My process was like below I configured wal_log_hints to on I restarted all the patroni nodes I checked wal_log_hints parameter in nodes that is ok Then tested problem with rebooting the leader node Mar 30, 2022 at 6:47
  • That is hard to believe. Mar 30, 2022 at 12:18

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