[pgpool-general: 6991] Re: Empty values for replication_state and replication_sync_state columns with pcp_node_info

[Tatsuo Ishii]

You need to set application name.
See https://www.pgpool.net/pipermail/pgpool-general/2020-April/007022.html

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

> Empty values for replication_state and replication_sync_state columns with
> pcp_node_info
> 
> Hello.
> 
> I have testing pgpool 4.1.1 with Postgresql 12.2 on Linux Centos 7.
> 
> I get empty values for replication_state and replication_sync_state columns
> with pcp_node_info or show pool_nodes.
> 
> I have two servers. I have configured Postgresql streaming replication and
> it's running with success. I get info for replication using sql sentence
> pg_stat_replication.
> For pgpool, I have configure backend_application_name0,
> backend_application_name1, sr_check_period (10) and sr_check_user (nobody).
> Using sr_check_user = postgres I get same results (empty values for
> replication_state and replication_sync_state columns).
> 
> What am I doing wrong?
> 
> Then I show some information:
> 
> 
> [root at server1 pgpool-II]# pcp_node_info --host 172.16.0.1 --port 9898
> --username admin -w --node-id 0
> 172.16.0.1 5432 2 0.500000 up primary 0   2020-04-20 09:38:04
> 
> [root at server1 pgpool-II]# pcp_node_info --host 172.16.0.1 --port 9898
> --username admin -w --node-id 1
> 172.16.0.2 5432 2 0.500000 up standby 0   2020-04-20 09:38:04
> 
> [root at server1 pgpool-II]# pcp_node_info --host 172.16.0.1 --port 9898
> --username admin -w --node-id 0 --verbose
> Hostname               : 172.16.0.1
> Port                   : 5432
> Status                 : 2
> Weight                 : 0.500000
> Status Name            : up
> Role                   : primary
> Replication Delay      : 0
> Replication State      :
> Replication Sync State :
> Last Status Change     : 2020-04-20 09:38:04
> [root at server1 pgpool-II]# pcp_node_info --host 172.16.0.1 --port 9898
> --username admin -w --node-id 1 --verbose
> Hostname               : 172.16.0.2
> Port                   : 5432
> Status                 : 2
> Weight                 : 0.500000
> Status Name            : up
> Role                   : standby
> Replication Delay      : 0
> Replication State      :
> Replication Sync State :
> Last Status Change     : 2020-04-20 09:38:04
> [root at server1 pgpool-II]#
> 
> 
> 
> [root at server1 ~]# psql -h 172.16.0.1 -p 9999 -U nobody -c "select * from
> pg_stat_replication" postgres
>  pid  | usesysid |  usename  | application_name | client_addr |
> client_hostname | client_port |         backend_start         | backen
> d_xmin |   state   |  sent_lsn  | write_lsn  | flush_lsn  | replay_lsn |
> write_lag | flush_lag | replay_lag | sync_priority | sync_sta
> te |          reply_time
> ------+----------+-----------+------------------+-------------+-----------------+-------------+-------------------------------+-------
> -------+-----------+------------+------------+------------+------------+-----------+-----------+------------+---------------+---------
> ---+-------------------------------
>  3664 |    16384 | userrepli | walreceiver      | 172.16.0.2  |
>     |       47482 | 2020-04-20 09:10:20.191692+02 |
>    522 | streaming | 0/19001298 | 0/19001298 | 0/19001298 | 0/19001298 |
>         |           |            |             0 | async
>    | 2020-04-20 09:33:32.341974+02
> (1 row)
> 
> [root at server1 ~]#
> 
> 
> [root at server1 ~]# pgpool -v
> pgpool-II version 4.1.1 (karasukiboshi)
> [root at server1 ~]#
> 
> [root at server1 ~]# psql -V
> psql (PostgreSQL) 12.2
> [root at server1 ~]#
> 
> 
> [root at server1 ~]# psql -h 172.16.0.1 -p 9999 -U nobody -c "pgpool show
> sr_check_period" postgres
>  sr_check_period
> -----------------
>  10
> (1 row)
> 
> [root at server1 ~]# psql -h 172.16.0.1 -p 9999 -U nobody -c "pgpool show
> sr_check_user" postgres
>  sr_check_user
> ---------------
>  nobody
> (1 row)
> 
> [root at server1 ~]#
> 
> [root at server1 ~]# psql -h 172.16.0.1 -p 9999 -U nobody -c "pgpool show
> backend_application_name0" postgres
>  backend_application_name0
> ---------------------------
>  server1
> (1 row)
> 
> [root at server1 ~]# psql -h 172.16.0.1 -p 9999 -U nobody -c "pgpool show
> backend_application_name1" postgres
>  backend_application_name1
> ---------------------------
>  server2
> (1 row)
> 
> [root at server1 ~]#
> 
> 
> [root at server1 ~]# psql -h 172.16.0.1 -p 9999 -U nobody -c "show pool_nodes"
> postgres
>  node_id |  hostname  | port | status | lb_weight |  role   | select_cnt |
> load_balance_node | replication_delay | replication_state |
>  replication_sync_state | last_status_change
> ---------+------------+------+--------+-----------+---------+------------+-------------------+-------------------+-------------------+
> ------------------------+---------------------
>  0       | 172.16.0.1 | 5432 | up     | 0.500000  | primary | 0          |
> true              | 0                 |                   |
>                         | 2020-04-20 09:23:40
>  1       | 172.16.0.2 | 5432 | up     | 0.500000  | standby | 0          |
> false             | 0                 |                   |
>                         | 2020-04-20 09:23:40
> (2 rows)
> 
> [root at server1 ~]#
> 
> Thanks in advance. Regards