> Hi Tatsuo, > > ok. now its working fine. thanks for your help. > > after getting through that initial setup for the first time, I'd like to > give you some feedback about the (at least for me) missing information in > the documentation. > > - please document the control flow during recovery, e.g. > connect to master server with recovery_user/recovery_password (connection > check) > run recovery_1st_stage_command > run checkpoint > run recovery_2nd_stage_command > ... > run failback_command > > - please document that recovery_1st_stage_command and > recovery_2nd_stage_command system calls by the current postgres masterserver > in the PGDATA directory are. And that the failback_command a shell script > command or system call from the pgpool server is. I needed to search for it > in the source code.
Sorry for inconvenience. I will add info to the docs as you suggested. > I have a different approach of recovering the postgres server. I'm > recovering from an existing backup. I do that because it is faster and I > don't put additional i/o load on the just activated server. I guess (or > hope) most people will have an existing backup. > > So my question is - if the aproach of recovering the failed server via a sql > command is optimal? What if both servers failed? then I'm not able to use > pcp-tools or pgpoolAdmin for recovering? I'm not sure what you are trying to do here. If "backup" means it was created by pg_dump_all, I don't think your approach works. Streaming replication requires a base backup(binary backup) which is managed by pg_start_backup/pg_stop_backup. > I'm asking because I worked for several years as an > it-production-responsible and I learned a little how administrators > think/work. They are happy if they have a (or better ONE) defined recovery > procedure. > Where am I getting? I'm asking you if it would makes sense to recode or > reduce the recovery procedure code to one system call e.g. failback_command. > Most people have their backup and restore functionality coded and ready for > training and/or desaster. If they could simply use this very same > functionality within pgpooladmin that would be great. > > It might be that i have overseen something (as before) and this is already > possible. If so please tell me how. > > Best Regards, > Uwe > > > On 26 April 2011 07:34, Tatsuo Ishii <[email protected]> wrote: > >> > thanks, that message already helped. I tried to recover the postgres >> server >> > with the failback_command. >> >> You are welcome. >> >> > I didn't realize these recovery_* parameters yet. >> > So I use the recovery_* parameters for recovering the failed postgres >> > server. >> >> pgpool-II connects to backend to issue some SQLs including CHECKPOINT. >> recovery_* parameters define the user and password for the connection. >> Usually they are for PostgreSQL super user (postgres). >> >> > And the failback_command to attach the postgres server into pgpool >> > right? >> >> If you want to do something special, for example mailing to DBA, then >> you might want to specify it. Otherwise you can leave it empty. >> -- >> Tatsuo Ishii >> SRA OSS, Inc. Japan >> English: http://www.sraoss.co.jp/index_en.php >> Japanese: http://www.sraoss.co.jp >> >> > Best Regards, >> > Uwe >> > >> > >> > On 26 April 2011 01:06, Tatsuo Ishii <[email protected]> wrote: >> > >> >> > I'm using pg-pool-II 3.0.3 with streaming replication. >> >> > I coded the failback scenario/script for the slave server and the >> script >> >> > itself works fine. >> >> > >> >> > I now configured the failback script in pgpool.conf and during testing >> an >> >> > error message comes up: >> >> > 2011-04-09 06:42:18 LOG: pid 16863: starting recovering node 1 >> >> > 2011-04-09 06:42:18 ERROR: pid 16863: start_recover: could not connect >> >> > master node. >> >> > >> >> > [root@adt-web01 pgpool-II-3.0.3]# pcp_node_info 10 adt-web01 9898 >> >> postgres >> >> > postgres 0 >> >> > adt-db01 5432 1 0.500000 >> >> > [root@adt-web01 pgpool-II-3.0.3]# pcp_node_info 10 adt-web01 9898 >> >> postgres >> >> > postgres 1 >> >> > adt-db02 5432 3 0.500000 >> >> > >> >> > pcp commands and pgpooladmin report that the master is up and running >> and >> >> > I'm able to connect to the master directly and through pgpool. >> >> > So what's wrong? So far everything else works fine. >> >> >> >> Assuming you have set recovery_user and recovery_passwd correctly, I'm >> >> not sure what's going on. IMO, the error message is very rare. It's so >> >> rare and there's a bug in the error path, which had not been found for >> >> long time. Can please try attached patch? The patch add a little bit >> >> usefull info to the error message above. >> >> -- >> >> Tatsuo Ishii >> >> SRA OSS, Inc. Japan >> >> English: http://www.sraoss.co.jp/index_en.php >> >> Japanese: http://www.sraoss.co.jp >> >> >> _______________________________________________ Pgpool-general mailing list [email protected] http://pgfoundry.org/mailman/listinfo/pgpool-general
