[pgpool-general: 5676] Re: find_primary_node problem

[Tatsuo Ishii]

From: Nagy Ákos <nagy.akos at libreoffice.ro>
Subject: Re: [pgpool-general: 5667] find_primary_node problem
Date: Wed, 2 Aug 2017 12:06:21 +0300
Message-ID: <fc3952a4-f53c-4abf-d717-c3f94f782134 at libreoffice.ro>

> 2017. 08. 02. 9:34 keltezéssel, Tatsuo Ishii írta:
>>> Hi,
>>>
>>> I installed a two member pgpool+postgresql cluster, and I have an
>>> interesting problem.
>>>
>>> I use LDX containers and ubuntu as OS, and after a clean install I can
>>> start pgpool2 without any problem, but after a service restart or
>>> failover, pgpool2 can't check the primary node from postgresql
>>> master-slave cluster.
>>>
>>> I got this error (and after 300 seconds - check interval - the pgpool2
>>> service remain started, but can't connect to postgresql, and can't
>>> determinate the master node):
>>>
>>> Aug  1 07:30:00 sd-ro-tm-dev-pg-01 pgpool[27998]: [27-1] 2017-08-01
>>> 07:30:00: pid 27998: LOG:  find_primary_node: checking backend no 0
>>> Aug  1 07:30:00 sd-ro-tm-dev-pg-01 pgpool[27998]: [28-1] 2017-08-01
>>> 07:30:00: pid 27998: LOG:  find_primary_node: checking backend no 1
>> No error logs found? Strange...
>>
>> Is it possible for you to enable debug log of Pgpool-II?
> Yes, I enable debug log, and I got:
> LOG:  find_primary_node: checking backend no 0
> LOG:  find_primary_node: checking backend no 1
> DEBUG:  pool_read: read 13 bytes from backend 0
> DEBUG:  authenticate kind = 5
> DEBUG:  pool_write: to backend: 0 kind:p
> DEBUG:  pool_read: read 318 bytes from backend 0
> DEBUG:  authenticate kind = 0
> DEBUG:  authenticate backend: key data received
> DEBUG:  authenticate backend: transaction state: I
> DEBUG:  do_query: extended:0 query:"SELECT pg_is_in_recovery()"
> DEBUG:  pool_write: to backend: 0 kind:Q
> DEBUG:  pool_read: read 75 bytes from backend 0
> DEBUG:  do_query: kind: 'T'
> DEBUG:  do_query: received ROW DESCRIPTION ('T')
> DEBUG:  do_query: row description: num_fileds: 1
> DEBUG:  do_query: kind: 'D'
> DEBUG:  do_query: received DATA ROW ('D')
> DEBUG:  do_query: kind: 'C'
> DEBUG:  do_query: received COMMAND COMPLETE ('C')
> DEBUG:  do_query: kind: 'Z'
> DEBUG:  do_query: received READY FOR QUERY ('Z')
> DEBUG:  pool_write: to backend: 0 kind:X
> DEBUG:  find_primary_node: 1 node is standby
> DEBUG:  find_primary_node: no primary node found
> 
> Manually I can connect from each pgpool host to each postgresql
> instance, and I can run this query: SELECT pg_is_in_recovery()
> On the primary node I got:
> pg_is_in_recovery
> -------------------
>  f
> (1 row)
> 
> and on the secondary:
>  pg_is_in_recovery
> -------------------
>  t
> (1 row)

Pgpool-II version?

Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp