Re: > 16TB worth of data question

On Mon, 2003-04-28 at 10:42, scott.marlowe wrote:
> On 28 Apr 2003, Jeremiah Jahn wrote:
>
> > On Fri, 2003-04-25 at 16:46, Jan Wieck wrote:
> > > Jeremiah Jahn wrote:
> > > >
> > > > On Tue, 2003-04-22 at 10:31, Lincoln Yeoh wrote:
[snip]
> Don't shut it down and backup at file system level, leave it up, restrict
> access via pg_hba.conf if need be, and use pg_dump. File system level
> backups are not the best way to go, although for quick recovery they can
> be added to full pg_dumps as an aid, but don't leave out the pg_dump,
> it's the way you're supposed to backup postgresql, and it can do so when
> the database is "hot and in use" and provide a consistent backup
> snapshot.

What's the problem with doing a file-level backup of a *cold* database?

The problem with pg_dump is that it's single-threaded, and it would take
a whole lotta time to back up 16TB using 1 tape drive...

If a pg database is spread across multiple devices (using symlinks),
then a cold database can be backed up, at the file level, using
multiple tape drives. (Of course, all symlinks would have to be
recreated when/if the database files had to be restored.)

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