[pgpool-general: 2668] Re: Restart Postgresql service

[Sergey Arlashin]

I tried different health check settings and used 

sudo -u postgres /usr/lib/postgresql/9.3/bin/pg_ctl -D /var/lib/postgresql/9.3/main/  restart -m fast

to restart postgresl, but still each time I restart one of postgresql backends I get something like this in pgpool.log:

Mar 27 19:13:35 lb-node1 pgpool[23886]: ProcessFrontendResponse: failed to read kind from frontend. frontend abnormally exited
Mar 27 19:13:35 lb-node1 pgpool[13960]: postmaster on DB node 1 was shutdown by administrative command
Mar 27 19:13:35 lb-node1 pgpool[32459]: postmaster on DB node 1 was shutdown by administrative command
Mar 27 19:13:35 lb-node1 pgpool[13960]: degenerate_backend_set: 1 fail over request from pid 13960
Mar 27 19:13:35 lb-node1 pgpool[32146]: postmaster on DB node 1 was shutdown by administrative command
Mar 27 19:13:35 lb-node1 pgpool[32459]: degenerate_backend_set: 1 fail over request from pid 32459
Mar 27 19:13:35 lb-node1 pgpool[32146]: degenerate_backend_set: 1 fail over request from pid 32146
Mar 27 19:13:35 lb-node1 pgpool[32187]: starting degeneration. shutdown host db-node2.site(5432)
Mar 27 19:13:35 lb-node1 pgpool[32187]: Restart all children
Mar 27 19:13:35 lb-node1 pgpool[4684]: postmaster on DB node 1 was shutdown by administrative command
Mar 27 19:13:35 lb-node1 pgpool[32187]: execute command: /etc/pgpool2/scripts/failover.sh 1 1 db-node1.site /var/lib/postgresql/9.3/main/switch_master
Mar 27 19:13:40 lb-node1 pgpool[32187]: find_primary_node_repeatedly: waiting for finding a primary node
Mar 27 19:13:44 lb-node1 pgpool[32187]: find_primary_node: primary node id is 0
Mar 27 19:13:44 lb-node1 pgpool[32187]: failover: set new primary node: 0
Mar 27 19:13:44 lb-node1 pgpool[32187]: failover: set new master node: 0
Mar 27 19:13:44 lb-node1 pgpool[4684]: degenerate_backend_set: 1 fail over request from pid 4684
Mar 27 19:13:44 lb-node1 pgpool[32295]: worker process received restart request
Mar 27 19:13:44 lb-node1 pgpool[32187]: failover done. shutdown host db-node2.site(5432)
Mar 27 19:13:45 lb-node1 pgpool[32289]: pcp child process received restart request
Mar 27 19:13:45 lb-node1 pgpool[32187]: PCP child 32289 exits with status 256 in failover()
Mar 27 19:13:45 lb-node1 pgpool[32187]: fork a new PCP child pid 15547 in failover()
Mar 27 19:13:45 lb-node1 pgpool[32187]: worker child 32295 exits with status 256
Mar 27 19:13:46 lb-node1 pgpool[32187]: fork a new worker child pid 15548
Mar 27 19:13:46 lb-node1 pgpool[32187]: failover: no backends are degenerated





On Mar 27, 2014, at 11:46 AM, Tatsuo Ishii <ishii at postgresql.org> wrote:

>> Hi!
>> Almost every time I restart backend postgresql service ( while pgpool is working ) it causes pgpool to mark this node as failed.
>> So I'm wondering if there is some 'proper' way to restart postgresql backends ( without stopping pgpool service ) which doesn't break the cluster. 
> 
> You can tweak health check parameters. For example,
> 
> health_check_max_retries = 10
> health_check_retry_delay = 1
> 
> Also make sure that you restart PostgreSQL with "fast" mode.
> 
> Best regards,
> --
> Tatsuo Ishii
> SRA OSS, Inc. Japan
> English: http://www.sraoss.co.jp/index_en.php
> Japanese: http://www.sraoss.co.jp