On Sat, Dec 18, 2010 at 10:23 PM, vvoody <wxj.g.sh@xxxxxxxxx> wrote: > I have two servers, one primary and one standby, which doing warm > standby. Every thing works fine at the beginning. The primary > generates the archive WAL log files and the standby fetchs them to > merge. > > Then, I want to let the standby become primary. So I stop the > postgresql(service postgresql stop) manually, copy the last WAL file > and files under pg_xlog/ to the standby. The former standby now > becomes primary and the data is ok. BTW, it still started as archive > mode. I follow you up to here. Presumably, you instantiated the standby using the steps outlined here: http://wiki.postgresql.org/wiki/Warm_Standby > Not end yet. After the standby running for a while and generating some > data, I want to switch back to the former primary. And I repeat the > above steps: stop the postgresql service manuall, copy WAL log files > and files under pg_xlog/ to the former primary. I delete the pg_xlog/ > and files under archive directory. Then the postgresql starts, but the > data generated after last switching do not come over. >From this description, it sounds like you're trying to shortcut the process of bringing your old primary server (server A) up-to-date with the currently-running server (server B). In order to bring server A up-to-date with B, you'll need to follow *all* the steps on that wiki page to set server A up as a warm standby of B, particularly the pg_start_backup(); rsync'ing of PGDATA over to A, etc. Josh -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
