Re: Backup routine

Christopher Browne wrote:
> The world rejoiced as peterandsarah@blueyonder.co.uk (Peter and Sarah Childs) wrote:
> >     However there is a third way. That should be safe but some
> > people may disagree with me! If you can "freeze" the disk while you
> > take the backup. The backup can be used as if the computer had
> > crashed with no hard disk failure at all. Ie WAL will be consistant
> > and database may take longer but once it is up it will be safe (like
> > paragaph 1). Now freezeing a disk for backup is not that
> > difficult. You should be doing it anyway for user file
> > consistancy. (You don't want the first 30 pages of you document to
> > disagree with the end because somone was saving it during the
> > backup!
>
> I heard D'Arcy Cain indicate that some SAN systems (I think he
> mentioned NetApp) support this sort of thing, too.  Digital's AdvFS
> also supports it.
>
> Of course, if you take this approach, you have to make _certain_ that
> when you "freeze" a replica of a filesystem, that _ALL_ of the
> database is contained in that one filesystem.  If you move WAL to a
> different filesystem, bets would be off again...

Also, I assume you have to stop the server just for a moment while you
do the freeze, right?

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