Hi,
Am Donnerstag, dem 10.03.2022 um 15:28 +0100 schrieb Gunnar "Nick"
Bluth:
> Am 10.03.22 um 14:43 schrieb Michael Banck:
> > some minor comments, I didn't look at the added test and I did not
> > test the patch at all, but (as part of the Debian/Ubuntu packaging
> > team) I think this patch is really important:
>
> Much appreciated!
>
> [...]
>
> Fixed.
>
> [...]
Thanks for the updated patch.
The patch applies, make is ok, make check is ok, pg_rewind TAP tests
are ok.
I did some tests now with Patroni 2.1.3 and the attached patch applied.
The following test was made:
1. Deploy 3-node (pg1, pg2, pg3) patroni cluster on Debian unstable
running postgresql-15 (approx. master)
2. Switch on archive_mode, and set archive_command and restore_command
3. Switchover so that pg1 is the primary (if not already)
4. Kill pg1 hard
5. Wait till a new leader has taken over and the (now 2-node) cluster
is healthy again
6. Restart pg1
without this patch:
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,084 INFO: running
pg_rewind from pg3
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,102 INFO: running
pg_rewind from dbname=postgres user=postgres_rewind host=10.0.3.227 port=5432
target_session_attrs=read-write
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,135 INFO:
pg_rewind exit code=1
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,136 INFO: stdout=
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,136 INFO:
stderr=postgres: could not access the server configuration file
"/var/lib/postgresql/15/main/postgresql.conf": No such file or directory
|Apr 03 19:09:01 pg1 patroni@15-main[99]: no data was returned by command
"/usr/lib/postgresql/15/bin/postgres -D /var/lib/postgresql/15/main -C
restore_command"
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,149 ERROR: Failed
to rewind from healty master: pg3
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,149 WARNING:
remove_data_directory_on_diverged_timelines is set. removing...
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,149 INFO:
Removing data directory: /var/lib/postgresql/15/main
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,245 INFO: Lock
owner: pg3; I am pg1
|Apr 03 19:09:01 pg1 patroni@15-main[99]: 2022-04-03 19:09:01,248 INFO: trying
to bootstrap from leader 'pg3'
So pg_rewind fails and Patroni does a re-bootstrap.
with this patch:
|Apr 03 19:12:35 pg1 patroni@15-main[99]: 2022-04-03 19:12:35,576 INFO: running
pg_rewind from pg2
|Apr 03 19:12:35 pg1 patroni@15-main[99]: 2022-04-03 19:12:35,590 INFO: running
pg_rewind from dbname=postgres user=postgres_rewind host=10.0.3.145 port=5432
target_session_attrs=read-write
|Apr 03 19:12:37 pg1 patroni@15-main[99]: 2022-04-03 19:12:37,147 INFO:
pg_rewind exit code=0
|Apr 03 19:12:37 pg1 patroni@15-main[99]: 2022-04-03 19:12:37,148 INFO: stdout=
|Apr 03 19:12:37 pg1 patroni@15-main[99]: 2022-04-03 19:12:37,148 INFO:
stderr=pg_rewind: servers diverged at WAL location 0/1D000180 on timeline 38
|Apr 03 19:12:37 pg1 patroni@15-main[99]: pg_rewind: rewinding from last common
checkpoint at 0/1D000108 on timeline 38
|Apr 03 19:12:37 pg1 patroni@15-main[99]: pg_rewind: Done!
|Apr 03 19:12:37 pg1 patroni@15-main[99]: 2022-04-03 19:12:37,151 WARNING:
Postgresql is not running.
|Apr 03 19:12:37 pg1 patroni@15-main[99]: 2022-04-03 19:12:37,151 INFO: Lock
owner: pg2; I am pg1
Here, pg_rewind is called and works fine.
So I think this works as intended, and I'm marking it Ready for
Committer.
Michael
--
Michael Banck
Teamleiter PostgreSQL-Team
Projektleiter
Tel.: +49 2166 9901-171
E-Mail: michael.ba...@credativ.de
credativ GmbH, HRB Mönchengladbach 12080
USt-ID-Nummer: DE204566209
Trompeterallee 108, 41189 Mönchengladbach
Geschäftsführung: Dr. Michael Meskes, Geoff Richardson, Peter Lilley
Unser Umgang mit personenbezogenen Daten unterliegt
folgenden Bestimmungen: https://www.credativ.de/datenschutz
--- /usr/lib/python3/dist-packages/patroni/postgresql/__init__.py 2022-02-18 13:16:15.000000000 +0000
+++ __init__.py 2022-04-03 19:17:29.952665383 +0000
@@ -798,7 +798,8 @@
return True
def get_guc_value(self, name):
- cmd = [self.pgcommand('postgres'), '-D', self._data_dir, '-C', name]
+ cmd = [self.pgcommand('postgres'), '-D', self._data_dir, '-C', name,
+ '--config-file={}'.format(self.config.postgresql_conf)]
try:
data = subprocess.check_output(cmd)
if data:
--- /usr/lib/python3/dist-packages/patroni/postgresql/rewind.py 2022-02-18 13:16:15.000000000 +0000
+++ rewind.py 2022-04-03 19:21:14.479726127 +0000
@@ -314,6 +314,7 @@
cmd = [self._postgresql.pgcommand('pg_rewind')]
if self._postgresql.major_version >= 130000 and restore_command:
cmd.append('--restore-target-wal')
+ cmd.append('--config-file={0}/postgresql.conf'.format(self._postgresql.config._config_dir))
cmd.extend(['-D', self._postgresql.data_dir, '--source-server', dsn])
while True:
