Thread: Re: How robust is postgresql ?

On Wed, 7 Mar 2001, John Madden wrote:

> Yum - can filesystem backups be done in 7.0.x?  (I would much prefer to
> killall -15 postmaster and copy files around than deal with pg_dump
> stuff.)  Or do I have to wait for 7.1?

I don't see why not -- you're just copying files.  The biggest issue with
the filesystem backup is making sure you get the correct logs backed up
also.

If you are upgrading between version, though, you have to use the pg_dump
way, as binary compatibility between versions is not guaranteed.

-- Brett
                http://www.chapelperilous.net/~bmccoy/
------------------------------------------------------------------------
Live free or die.

Thanks for the answer, (and thanks to adb too)
>
> 7.1 has write-ahead logging (WAL), which does what you are looking for.
> See http://www.postgresql.org/devel-corner/docs/admin/wal.html
>
> The fsync mode also helps with data integiry, but it *really* slows down
> the system, unfortunately.

Looks like WAL is what we want. I understand that 7.1 should be out in a few
weeks ?

> > The other question is Backups. Is there anyway to take diferential
backups ?
> > I.E do a full dump periodically, and then make diferential backups from
time
> > to time (preferably to a differet box)
>
> You can do a database dump and back up the SQL generated, or do a
> filesystem backup.  See
> http://www.postgresql.org/devel-corner/docs/admin/backup.html for
> information on the specifics.

I was looking for ways of backing up only data that had changed since the
last backup. The server will probably be hosted with an ISP so I don't want
unnecessary data transfers.