On Mon, Dec 20, 2010 at 12:22 PM, Iñigo Martinez Lasala <imartinez@xxxxxxxxxxxx> wrote: > Good evening. > > Yesterday we experienced some data duplication in several database tables > after one sysadmin decided to test in a production environment an rsync > script in order to migrate a database from one server to another one. > Postgresql (8.2) was running in source server and rsync script was launched > from second one. Second one server had a one day old copy of the same > database. Rsync script create a datafile replica in destination server. > Our sysadmin swear he didn't launch the script in a reverse way (that is, > from destination to source)... so my question is > How this data duplication could happen? Due to an rsync lock in checkpoint > segment or transaction logs? Or he has mistaken source with destination > server? I use this method all the time to backup big dbs from one machine to another: (on remote machine): /etc/init.d/postgresql stop (on main server): rsync -avl --delete /data/* backupserver:/data/* # takes forever sudo /etc/init.d/postgresql stop rsync -avl --delete /data/* backupserver:/data/* # fast, we're just catching up sudo /etc/init.d/postgresql start (on remote machine): /etc/init.d/postgresql start You can run such a script at 2 in the morning with a few minutes downtime without having to jump through a lot of hoops. So, can you show us what commands your sysadmin / dba actually typed? My guess is he left out the --delete or left the backup server db up and running at the time of the rsync. It needs to be shut down to do this right. -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
