[pgpool-general: 1407] Re: pgPool Online Recovery Streaming Replication
ning chan
ninchan8328 at gmail.com
Wed Feb 20 06:02:59 JST 2013
Hi Tatsuo,
I figured out the problem to the some scripting error in the
pgpool_remote_start to have the incorrect path to pg_ctl.
As soon as I corrected it i can recover the failed server and bring it
online.
I now however facing another problem.
After I bring the failed master back in to the pgpool as a standby server,
i then shutdown the currect Primary server and expecting Standby server
will be promoted to become the new Primary; however it did not happen.
I check the pgpool log, i see failover command is called but it did not
execute. I check and confirm my failover script works just fine.
Here is the log:
Feb 19 14:51:40 server0 pgpool[3519]: set 1 th backend down status
Feb 19 14:51:43 server0 pgpool[3554]: wd_create_send_socket: connect()
reports failure (No route to host). You can safely ignore this while
starting up.
Feb 19 14:51:43 server0 pgpool[3522]: wd_lifecheck: lifecheck failed 3
times. pgpool seems not to be working
Feb 19 14:51:43 server0 pgpool[3522]: wd_IP_down: ifconfig down succeeded
Feb 19 14:51:43 server0 pgpool[3519]: starting degeneration. shutdown host
server1(5432)
Feb 19 14:51:43 server0 pgpool[3519]: Restart all children
Feb 19 14:51:43 server0 pgpool[3519]: execute command:
/home/pgpool/failover.py -d 1 -h server1 -p 5432 -D /opt/postgres/9.2/data
-m 0 -H server0 -M 0 -P 1 -r 5432 -R /opt/postgres/9.2/data
Feb 19 14:51:43 server0 postgres[3939]: [2-1] LOG: incomplete startup
packet
Feb 19 14:51:43 server0 postgres[3931]: [2-1] LOG: incomplete startup
packet
Feb 19 14:51:43 server0 postgres[3935]: [2-1] LOG: incomplete startup
packet
Feb 19 14:51:43 server0 pgpool[3519]: find_primary_node_repeatedly: waiting
for finding a primary node
Feb 19 14:51:46 server0 pgpool[3522]: wd_create_send_socket: connect()
reports failure (No route to host). You can safely ignore this while
starting up.
Feb 19 14:51:46 server0 pgpool[3522]: wd_lifecheck: lifecheck failed 3
times. pgpool seems not to be working
Feb 19 14:51:54 server0 pgpool[3556]: connect_inet_domain_socket: connect()
failed: Connection timed out
Feb 19 14:51:54 server0 pgpool[3556]: make_persistent_db_connection:
connection to server1(5432) failed
Feb 19 14:51:54 server0 pgpool[3556]: check_replication_time_lag: could not
connect to DB node 1, check sr_check_user and sr_check_password
Feb 19 14:52:05 server0 pgpool[3522]: wd_lifecheck: lifecheck failed 3
times. pgpool seems not to be working
Feb 19 14:52:05 server0 pgpool[3556]: connect_inet_domain_socket: connect()
failed: No route to host
Feb 19 14:52:05 server0 pgpool[3556]: make_persistent_db_connection:
connection to server1(5432) failed
Feb 19 14:52:05 server0 pgpool[3556]: check_replication_time_lag: could not
connect to DB node 1, check sr_check_user and sr_check_password
Feb 19 14:52:05 server0 pgpool[3522]: wd_lifecheck: lifecheck failed 3
times. pgpool seems not to be working
Feb 19 14:52:14 server0 pgpool[3519]: failover: no follow backends are
degenerated
Feb 19 14:52:14 server0 pgpool[3519]: failover: set new primary node: -1
Feb 19 14:52:14 server0 pgpool[3519]: failover: set new master node: 0
Feb 19 14:52:14 server0 pgpool[3980]: connection received:
host=server0.local port=45361
Feb 19 14:52:14 server0 pgpool[3556]: worker process received restart
request
Feb 19 14:52:14 server0 pgpool[3519]: failover done. shutdown host
server1(5432)
As you can see, postgreSQL did not restarted.
>From a successful failover, the log should looks like this:
Feb 19 13:47:01 server0 pgpool[4391]: execute command:
/home/pgpool/failover.py -d 1 -h server1 -p 5432 -D /opt/postgres/9.2/data
-m 0 -H server0 -M 0 -P 1 -r 5432 -R /opt/postgres/9.2/data
Feb 19 13:47:01 server0 postgres[4786]: [2-1] LOG: incomplete startup
packet
Feb 19 13:47:02 server0 pgpool[4391]: find_primary_node_repeatedly: waiting
for finding a primary node
Feb 19 13:47:06 server0 postgres[3083]: [6-1] LOG: trigger file found:
/opt/postgres/9.2/data/trigger_file0
Feb 19 13:47:06 server0 postgres[3083]: [7-1] LOG: redo done at 0/91000020
Feb 19 13:47:06 server0 postgres[3083]: [8-1] LOG: selected new timeline
ID: 18
Feb 19 13:47:06 server0 postgres[3083]: [9-1] LOG: archive recovery
complete
Feb 19 13:47:06 server0 postgres[3081]: [2-1] LOG: database system is
ready to accept connections
Feb 19 13:47:06 server0 postgres[4804]: [2-1] LOG: autovacuum launcher
started
Feb 19 13:47:07 server0 pgpool[4391]: find_primary_node: primary node id is
0
Feb 19 13:47:07 server0 pgpool[4391]: starting follow degeneration.
shutdown host server1(5432)
Feb 19 13:47:07 server0 pgpool[4391]: failover: 1 follow backends have been
degenerated
Feb 19 13:47:07 server0 pgpool[4391]: failover: set new primary node: 0
Feb 19 13:47:07 server0 pgpool[4391]: failover: set new master node: 0
Feb 19 13:47:07 server0 pgpool[4817]: connection received:
host=server1.local port=54619
Feb 19 13:47:07 server0 pgpool[4816]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4818]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4819]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4815]: start triggering follow command.
Feb 19 13:47:07 server0 pgpool[4815]: execute command: echo 1 server1 5432
/opt/postgres/9.2/data 0 server0 0 1 5432 /opt/postgres/9.2/data %
Feb 19 13:47:07 server0 pgpool[4821]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4822]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4823]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4820]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4827]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4828]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4826]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4829]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4830]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4831]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4832]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4833]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4834]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4833]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4834]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4835]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4836]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4837]: do_child: failback event found.
restart myself.
Feb 19 13:47:07 server0 pgpool[4391]: failover done. shutdown host
server1(5432)
Any idea why failover did not work after the recovery? Do i need to restart
remote pgpool after recovery?
On Mon, Feb 18, 2013 at 4:24 PM, ning chan <ninchan8328 at gmail.com> wrote:
>
> Hi Tatsuo,
> Sorry for the late reply as I was traveling.
> I am able to reproduce the problem and here is what I did:
>
> *1) Make sure primary (server0) and standby (server1) connections are
> good.*
> [root at server0 tmp]# psql -c "show pool_nodes" -p 9999
> node_id | hostname | port | status | lb_weight | role
> ---------+----------+------+--------+-----------+---------
> 0 | server0 | 5432 | 2 | 0.500000 | primary
> 1 | server1 | 5432 | 2 | 0.500000 | standby
> (2 rows)
>
> [root at server1 tmp]# psql -c "show pool_nodes" -p 9999
> node_id | hostname | port | status | lb_weight | role
> ---------+----------+------+--------+-----------+---------
> 0 | server0 | 5432 | 2 | 0.500000 | primary
> 1 | server1 | 5432 | 2 | 0.500000 | standby
> (2 rows)
>
> *2) force shutdown primary (server0), and standby (server1) server was
> promoted, below is the pgpool log from server1 during the failover:*
> Feb 18 15:31:45 server1 pgpool[2691]: connect_inet_domain_socket:
> connect() failed: No route to host
> Feb 18 15:31:45 server1 pgpool[2691]: make_persistent_db_connection:
> connection to server0(5432) failed
> Feb 18 15:31:45 server1 pgpool[2691]: check_replication_time_lag: could
> not connect to DB node 0, check sr_check_user and sr_check_password
> Feb 18 15:31:45 server1 pgpool[2689]: connect_inet_domain_socket:
> connect() failed: No route to host
> Feb 18 15:31:45 server1 pgpool[2689]: connection to server0(5432) failed
> Feb 18 15:31:45 server1 pgpool[2689]: new_connection: create_cp() failed
> Feb 18 15:31:45 server1 pgpool[2689]: degenerate_backend_set: 0 fail over
> request from pid 2689
> Feb 18 15:31:48 server1 pgpool[2689]: wd_create_send_socket: connect()
> reports failure (No route to host). You can safely ignore this while
> starting up.
> Feb 18 15:31:48 server1 pgpool[2653]: connect_inet_domain_socket:
> connect() failed: No route to host
> Feb 18 15:31:48 server1 pgpool[2653]: make_persistent_db_connection:
> connection to server0(5432) failed
> Feb 18 15:31:48 server1 pgpool[2653]: health check failed. 0 th host
> server0 at port 5432 is down
> Feb 18 15:31:48 server1 pgpool[2653]: health check retry sleep time: 5
> second(s)
> Feb 18 15:31:48 server1 pgpool[2653]: starting degeneration. shutdown host
> server0(5432)
> Feb 18 15:31:48 server1 pgpool[2653]: Restart all children
> Feb 18 15:31:48 server1 pgpool[2653]: execute command:
> /home/pgpool/failover.py -d 0 -h server0 -p 5432 -D /opt/postgres/9.2/data
> -m 1 -H server1 -M 0 -P 0 -r 5432 -R /opt/postgres/9.2/data
> Feb 18 15:31:49 server1 pgpool[2653]: find_primary_node_repeatedly:
> waiting for finding a primary node
> Feb 18 15:31:53 server1 postgres[1970]: [7-1] LOG: trigger file found:
> /tmp/trigger_file0
> Feb 18 15:31:53 server1 postgres[2597]: [3-1] FATAL: terminating
> walreceiver process due to administrator command
> Feb 18 15:31:53 server1 postgres[1970]: [8-1] LOG: record with zero
> length at 0/64000418
> Feb 18 15:31:53 server1 postgres[1970]: [9-1] LOG: redo done at 0/640003B8
> Feb 18 15:31:53 server1 postgres[1970]: [10-1] LOG: selected new timeline
> ID: 15
> Feb 18 15:31:53 server1 postgres[1970]: [11-1] LOG: archive recovery
> complete
> Feb 18 15:31:53 server1 postgres[1968]: [2-1] LOG: database system is
> ready to accept connections
> Feb 18 15:31:53 server1 postgres[3168]: [2-1] LOG: autovacuum launcher
> started
> Feb 18 15:31:54 server1 pgpool[2653]: find_primary_node: primary node id
> is 1
> Feb 18 15:31:54 server1 pgpool[2653]: starting follow degeneration.
> shutdown host server0(5432)
> Feb 18 15:31:54 server1 pgpool[2653]: failover: 1 follow backends have
> been degenerated
> Feb 18 15:31:54 server1 pgpool[2653]: failover: set new primary node: 1
> Feb 18 15:31:54 server1 pgpool[2653]: failover: set new master node: 1
> Feb 18 15:31:54 server1 pgpool[3171]: connection received:
> host=server1.local port=58346
> Feb 18 15:31:54 server1 pgpool[3170]: start triggering follow command.
> Feb 18 15:31:54 server1 pgpool[3170]: execute command: echo 0 server0 5432
> /opt/postgres/9.2/data 1 server1 0 0 5432 /opt/postgres/9.2/data %
> Feb 18 15:31:54 server1 pgpool[2691]: worker process received restart
> request
> Feb 18 15:31:54 server1 pgpool[2653]: failover done. shutdown host
> server0(5432)
>
> *3) boot up the failed server (server0) as usual, pgpool and database
> started up as usual.
> *
> *after server0 boot up, i check the pool_nodes info, server0 pgpool still
> think server0 is the primary:*
> [root at server0 ~]# psql -c "show pool_nodes" -p 9999
> node_id | hostname | port | status | lb_weight | role
> ---------+----------+------+--------+-----------+---------
> 0 | server0 | 5432 | 2 | 0.500000 | primary
> 1 | server1 | 5432 | 2 | 0.500000 | standby
> (2 rows)
>
> server1 pgpool still think server1 is the primary:
> [root at server1 tmp]# psql -c "show pool_nodes" -p 9999
> node_id | hostname | port | status | lb_weight | role
> ---------+----------+------+--------+-----------+---------
> 0 | server0 | 5432 | 3 | 0.500000 | standby
> 1 | server1 | 5432 | 2 | 0.500000 | primary
> (2 rows)
>
> *4) kill the database on server0 to prepare of the recovery*
> *as soon as i kill the server0 database, pgpool log shows following:*
> Feb 18 15:33:56 server0 pgpool[2153]: execute command:
> /home/pgpool/failover.py -d 0 -h server0 -p 5432 -D /opt/postgres/9.2/data
> -m 1 -H server1 -M 0 -P 0 -r 5432 -R /opt/postgres/9.2/data
> Feb 18 15:33:57 server0 pgpool[2153]: find_primary_node_repeatedly:
> waiting for finding a primary node
> Feb 18 15:33:57 server0 pgpool[2153]: find_primary_node: primary node id
> is 1
> Feb 18 15:33:57 server0 pgpool[2153]: starting follow degeneration.
> shutdown host server0(5432)
> Feb 18 15:33:57 server0 pgpool[2153]: failover: 1 follow backends have
> been degenerated
> Feb 18 15:33:57 server0 pgpool[2153]: failover: set new primary node: 1
> Feb 18 15:33:57 server0 pgpool[2153]: failover: set new master node: 1
> Feb 18 15:33:57 server0 pgpool[2534]: start triggering follow command.
> Feb 18 15:33:57 server0 pgpool[2534]: execute command: echo 0 server0 5432
> /opt/postgres/9.2/data 1 server1 0 0 5432 /opt/postgres/9.2/data %
> Feb 18 15:33:57 server0 pgpool[2190]: worker process received restart
> request
> Feb 18 15:33:57 server0 pgpool[2153]: failover done. shutdown host
> server0(5432)
>
> pool_nodes shows:
> [root at server0 ~]# psql -c "show pool_nodes" -p 9999
> node_id | hostname | port | status | lb_weight | role
> ---------+----------+------+--------+-----------+---------
> 0 | server0 | 5432 | 3 | 0.500000 | standby
> 1 | server1 | 5432 | 2 | 0.500000 | primary
> (2 rows)
>
>
> *5) on server1, execute /usr/local/bin/pcp_recovery_node 10 localhost
> 9898 pgpool password 0*
> server 1 pgpool log shows following:
> Feb 18 15:34:52 server1 pgpool[3209]: starting recovery command: "SELECT
> pgpool_recovery('basebackup.sh', 'server0', '/opt/postgres/9.2/data')"
> Feb 18 15:34:53 server1 pgpool[3209]: 1st stage is done
> Feb 18 15:34:53 server1 pgpool[3209]: check_postmaster_started: try to
> connect to postmaster on hostname:server0 database:postgres user:postgres
> (retry 0 times)
> Feb 18 15:34:53 server1 pgpool[3209]: check_postmaster_started: failed to
> connect to postmaster on hostname:server0 database:postgres user:postgres
>
> *The message "fail to connect to postmaster on hostname server0" continue
> until the command timeout.
> *
> *it looks like the 1st stage command is done but pgpool on server1 did
> not call the pgpool_remote_start to start the server0 database engine
> although the script is there under postgresql data folder
> *
> [root at server1 data]# ls
> backup_label.old data pg_hba.conf pg_notify
> pg_stat_tmp PG_VERSION postmaster.pid
> base global pg_ident.conf pgpool_remote_start
> pg_subtrans pg_xlog recovery.done
> basebackup.sh ning.test pg_log pg_serial
> pg_tblspc postgresql.conf recovery.standby1
> copy-base-backup.sh pg_clog pg_multixact pg_snapshots
> pg_twophase postmaster.opts
>
> *during this period, pgpool log on server0 shows the following:*
> Feb 18 15:34:42 server0 pgpool[2567]: connection received:
> host=server0.local port=45366
> Feb 18 15:34:46 server0 pgpool[2567]: connection received:
> host=server1.local port=39535
> Feb 18 15:34:52 server0 pgpool[2567]: connection received:
> host=server0.local port=45381
> Feb 18 15:34:56 server0 pgpool[2565]: connection received:
> host=server1.local port=39557
> Feb 18 15:35:02 server0 pgpool[2565]: connection received:
> host=server0.local port=45396
> Feb 18 15:35:06 server0 pgpool[2565]: connection received:
> host=server1.local port=39576
> Feb 18 15:35:12 server0 pgpool[2565]: connection received:
> host=server0.local port=45410
> Feb 18 15:35:16 server0 pgpool[2565]: connection received:
> host=server1.local port=39593
> Feb 18 15:35:22 server0 pgpool[2565]: connection received:
> host=server0.local port=45425
> Feb 18 15:35:26 server0 pgpool[2565]: connection received:
> host=server1.local port=39612
> Feb 18 15:35:32 server0 pgpool[2565]: connection received:
> host=server0.local port=45440
> Feb 18 15:35:36 server0 pgpool[2565]: connection received:
> host=server1.local port=39630
> Feb 18 15:35:42 server0 pgpool[2565]: connection received:
> host=server0.local port=45455
> Feb 18 15:35:46 server0 pgpool[2565]: connection received:
> host=server1.local port=39648
>
> *Below is the script of recovery_1st_stage_command = 'basebackup.sh'*
> [root at server1 ~]# more /opt/postgres/9.2/data/basebackup.sh
> #! /bin/sh
> # Recovery script for streaming replication.
> # This script assumes that DB node 0 is primary, and 1 is standby.
> #
> datadir=$1
> desthost=$2
> destdir=$3
>
> echo "datadir=$datadir"
> echo "desthost=$desthost"
> echo "destdir=$destdir"
>
> echo "Executing basebackup.sh" >> /var/log/replication.log
>
> echo "Executing start backup" >> /var/log/replication.log
> psql -c "SELECT pg_start_backup('Streaming Replication', true)" postgres
>
> echo "Executing rsync" >> /var/log/replication.log
> echo "rsync -C -a --progress --delete -e ssh --exclude postgresql.conf
> --exclude postmaster.pid --exclude postmaster.
> opts --exclude pg_log --exclude pg_xlog --exclude recovery.conf $datadir/
> $desthost:$destdir/"
>
> echo "Renaming recovery conf file" >>/var/log/replication.log
> echo "ssh -T $desthost mv $destdir/recovery.done $destdir/recovery.conf"
> ssh -T $desthost mv $destdir/recovery.done $destdir/recovery.conf
>
> echo "Removing trigger file"
> ssh -T $desthost rm -f /tmp/trigger_file0
>
> echo "Executing stop backup" >> /var/log/replication.log
> psql -c "SELECT pg_stop_backup()" postgres
>
> echo "existing basebackup.sh" >> /var/log/replication.log
>
> *Manually execute the command on server1 return the following result:*
>
> [root at server1 data]# ./basebackup.sh /opt/postgres/9.2/data/ server0
> /opt/postgres/9.2/data/
> datadir=/opt/postgres/9.2/data/
> desthost=server0
> destdir=/opt/postgres/9.2/data/
> pg_start_backup
> -----------------
> 0/76000020
> (1 row)
>
> rsync -C -a --progress --delete -e ssh --exclude postgresql.conf --exclude
> postmaster.pid --exclude postmaster.opts --exclude pg_log --exclude pg_xlog
> --exclude recovery.conf /opt/postgres/9.2/data//
> server0:/opt/postgres/9.2/data//
> ssh -T server0 mv /opt/postgres/9.2/data//recovery.done
> /opt/postgres/9.2/data//recovery.conf
> Removing trigger file
> NOTICE: WAL archiving is not enabled; you must ensure that all required
> WAL segments are copied through other means to complete the backup
> pg_stop_backup
> ----------------
> 0/760000E0
> (1 row)
>
> Thanks and please advise.
>
> Ning
>
>
> On Sun, Feb 17, 2013 at 7:05 AM, Tatsuo Ishii <ishii at postgresql.org>wrote:
>
>> Hi,
>>
>> It seems the standby was unable to start up. Can you show standby
>> PostgreSQL's log? Maybe we could find the cause of the problem.
>> --
>> Tatsuo Ishii
>> SRA OSS, Inc. Japan
>> English: http://www.sraoss.co.jp/index_en.php
>> Japanese: http://www.sraoss.co.jp
>>
>> > Hi Tatsuo,
>> > Thank you so much for your reply.
>> > Actually in my case, i was using the pcp_recovery command and execute
>> it on
>> > the current primary server.
>> > However, if the remote node (recover node) database is off, i got the
>> > following message on the primary server pgpool log:
>> >
>> > Jan 31 16:58:10 server0 pgpool[2723]: starting recovery command: "SELECT
>> > pgpool_recovery('basebackup.sh', 'server1', '/opt/postgres/9.2/data')"
>> > Jan 31 16:58:11 server0 pgpool[2723]: 1st stage is done
>> > Jan 31 16:58:11 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:postgres
>> user:postgres
>> > (retry 0 times)
>> > Jan 31 16:58:11 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:postgres
>> user:postgres
>> > Jan 31 16:58:13 server0 pgpool[2719]: connection received:
>> > host=server0.local port=58446
>> > Jan 31 16:58:14 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:postgres
>> user:postgres
>> > (retry 1 times)
>> > Jan 31 16:58:14 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:postgres
>> user:postgres
>> > Jan 31 16:58:14 server0 pgpool[2719]: connection received:
>> > host=server1.local port=39928
>> > Jan 31 16:58:17 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:postgres
>> user:postgres
>> > (retry 2 times)
>> > Jan 31 16:58:17 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:postgres
>> user:postgres
>> > Jan 31 16:58:20 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:postgres
>> user:postgres
>> > (retry 3 times)
>> > Jan 31 16:58:20 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:postgres
>> user:postgres
>> > Jan 31 16:58:23 server0 pgpool[2719]: connection received:
>> > host=server0.local port=58464
>> > Jan 31 16:58:23 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > (retry 0 times)
>> > Jan 31 16:58:23 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > Jan 31 16:58:26 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > (retry 1 times)
>> > Jan 31 16:58:26 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > Jan 31 16:58:26 server0 pgpool[2719]: connection received:
>> > host=server1.local port=39946
>> > Jan 31 16:58:29 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > (retry 2 times)
>> > Jan 31 16:58:29 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > Jan 31 16:58:32 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > (retry 3 times)
>> > Jan 31 16:58:32 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > Jan 31 16:58:33 server0 pgpool[2719]: connection received:
>> > host=server0.local port=58483
>> > Jan 31 16:58:35 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > (retry 4 times)
>> > Jan 31 16:58:35 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > Jan 31 16:58:38 server0 pgpool[2723]: check_postmaster_started: try to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> > (retry 5 times)
>> > Jan 31 16:58:38 server0 pgpool[2723]: check_postmaster_started: failed
>> to
>> > connect to postmaster on hostname:server1 database:template1
>> user:postgres
>> >
>> > here is the exact command i execute on server0 to recover server1,
>> > /usr/local/bin/pcp_recovery_node 10 localhost 9898 pgpool password 1
>> >
>> > Do you have any idea why?
>> >
>> > Just FYI, we cannot pgpoolAdmin in our environment.
>> >
>> >
>> > On Sun, Feb 17, 2013 at 12:13 AM, Tatsuo Ishii <ishii at postgresql.org>
>> wrote:
>> >
>> >> > Hi all,
>> >> > I have the following question regarding the recovery of a filed
>> Primary
>> >> > Database Server.
>> >> >
>> >> > Question 1: in the documentation, under Streaming Replication Online
>> >> > Recovery section.
>> >> >
>> >> > http://www.pgpool.net/docs/latest/pgpool-en.html#stream
>> >> >
>> >> > in steps 6:
>> >> >
>> >> > 1. After completing online recovery, pgpool-II will start
>> PostgreSQL
>> >> on
>> >> > the standby node. Install the script for this purpose on each DB
>> >> > nodes. Sample
>> >> > script <http://www.pgpool.net/docs/latest/pgpool_remote_start> is
>> >> > included in "sample" directory of the source code. This script
>> uses
>> >> ssh.
>> >> > You need to allow recovery_user to login from the primary node to
>> the
>> >> > standby node without being asked password.
>> >> >
>> >> > To my understanding, i think the postgreSQL doesn't not need to be
>> online
>> >> > for the recovery process right? Since later on it mentions that
>> >> > pgpool_remote_start will start up the DB on the failed node.
>> >>
>> >> Acually standby PostgreSQL node should not be started.
>> >>
>> >> > Question 2: in my configuration, i have 2 pgpool server with two
>> >> backends.
>> >> > Will it work for oneline recovery?
>> >>
>> >> Yes, but online recovery process should be initiated by one of pgpool,
>> >> not both. If you enable pgpool-II 3.2's watchdog, it will take care of
>> >> neccessary interlocking.
>> >>
>> >> > Question 3: when the failed node comes back online, should i use
>> >> > pcp_recovery from DB primary or should i use pcp_attach on the failed
>> >> node
>> >> > to recover the failed system? Actually in my case, both methods do
>> not
>> >> > recover my system every time.
>> >>
>> >> I'm confused. Didn't you start the online recovery process by using
>> >> pcp_recovery_node?(of course you could do it via pgpoolAdmin).
>> >>
>> >> Anyway pcp_recovery_node automatically attach recovered node, and you
>> >> don't need to execute pcp_attach_node.
>> >>
>> >> I suggest you read tutorial:
>> >>
>> http://www.pgpool.net/pgpool-web/contrib_docs/simple_sr_setting2/index.html
>> >> --
>> >> Tatsuo Ishii
>> >> SRA OSS, Inc. Japan
>> >> English: http://www.sraoss.co.jp/index_en.php
>> >> Japanese: http://www.sraoss.co.jp
>> >>
>>
>
>
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