Re: [GENERAL] File system level copy
My purpose is not to do backup for my database. I just want to copy the whole db3 database to another machine and restore it. That database could be very large so I think directly copy is more efficient than pg_dump. So I'd like to do some test to see if this way works. If it doesn't work, I will consider to use pg_dump. Thank you for your feedback. -Original Message- From: pgsql-general-ow...@postgresql.org [mailto:pgsql-general-ow...@postgresql.org] On Behalf Of Albe Laurenz Sent: Thursday, November 15, 2012 4:52 PM To: Wang, Hao; pgsql-general@postgresql.org Subject: Re: [GENERAL] File system level copy Hao Wang wrote: I installed PostgresSQL-8.3 on my linux machine. The cluster directory is /usr/local/data and I created three databases named db1, db2, and db3. db1 is in the default tablespace 'pg_default'. db2 is in '/home/tablespace/space1/' and db3 is in '/home/tablespace/space2/'. I want to copy the cluster directory and the db3 tablespace folder('/home/tablespace/space2/') without stopping the database server. Then I want to use the cluster directory and db3's tablespace in another linux machine to recover 'db3' database. Does this way work? If not, why? First, you need a correct backup for recovery. Before copying, run pg_start_backup, and pg_stop_backup afterwards. Then you need to have recovery.conf and WAL archives (or be lucky and all WALs are still in pg_xlog). WAL contains changes to all databases in the cluster, so you cannot recover only one database, you'll have to recover them all. Read http://www.postgresql.org/docs/current/static/continuous-archiving.html for background and details. This is PITR, right? I don't want to use this way because I'm not allowed to change the configuration parameter of database server. I just want to use some whole DB copy to restore db3 in another machine. And I don't want to use pg_dump because I think db3 is so large that pg_dump will probably have bad performance. That's a whole lot of arbitrary restrictions. If all you want is a copy of the database, pg_dump is what you should use. Besides, it is the only way to get a copy of just one database. What's the problem if pg_dump takes a few hours or days (I don't know how big you DB is)? A side thought: if the DB is not configured for PITR and pg_dump takes too long, how do you perform your backups? Yours, Laurenz Albe -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
[GENERAL] File system level copy
Hi I installed PostgresSQL-8.3 on my linux machine. The cluster directory is /usr/local/data and I created three databases named db1, db2, and db3. db1 is in the default tablespace 'pg_default'. db2 is in '/home/tablespace/space1/' and db3 is in '/home/tablespace/space2/'. I want to copy the cluster directory and the db3 tablespace folder('/home/tablespace/space2/') without stopping the database server. Then I want to use the cluster directory and db3's tablespace in another linux machine to recover 'db3' database. Does this way work? If not, why? Regards, Hao
[GENERAL] File system level copy
Hi, I installed PostgresSQL-8.3 on my linux machine. The cluster directory is /usr/local/data and I created three databases named db1, db2, and db3. db1 is in the default tablespace 'pg_default'. db2 is in '/home/tablespace/space1/' and db3 is in '/home/tablespace/space2/'. I want to copy the cluster directory and the db3 tablespace folder('/home/tablespace/space2/') without stopping the database server. Then I want to use the cluster directory and db3's tablespace in another linux machine to recover 'db3' database. Does this way work? If not, why?
Re: [GENERAL] File system level copy
This is PITR, right? I don't want to use this way because I'm not allowed to change the configuration parameter of database server. I just want to use some whole DB copy to restore db3 in another machine. And I don't want to use pg_dump because I think db3 is so large that pg_dump will probably have bad performance. -Original Message- From: Albe Laurenz [mailto:laurenz.a...@wien.gv.at] Sent: Wednesday, November 14, 2012 6:49 PM To: Wang, Hao; pgsql-general@postgresql.org Subject: RE: [GENERAL] File system level copy Hao Wang wrote: I installed PostgresSQL-8.3 on my linux machine. The cluster directory is /usr/local/data and I created three databases named db1, db2, and db3. db1 is in the default tablespace 'pg_default'. db2 is in '/home/tablespace/space1/' and db3 is in '/home/tablespace/space2/'. I want to copy the cluster directory and the db3 tablespace folder('/home/tablespace/space2/') without stopping the database server. Then I want to use the cluster directory and db3's tablespace in another linux machine to recover 'db3' database. Does this way work? If not, why? First, you need a correct backup for recovery. Before copying, run pg_start_backup, and pg_stop_backup afterwards. Then you need to have recovery.conf and WAL archives (or be lucky and all WALs are still in pg_xlog). WAL contains changes to all databases in the cluster, so you cannot recover only one database, you'll have to recover them all. Read http://www.postgresql.org/docs/current/static/continuous-archiving.html for background and details. Yours, Laurenz Albe -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general