Re: Help recovering from hotbackup

"Howard J. Rogers" <howardjr2000_at_yahoo.com.au> wrote in message news:osNM9.7412$jM5.20748_at_newsfeeds.bigpond.com...
> > Howard,
> >
> > Go easy, please.
> >
> > What happens if you lose all the online redo logs (yes I know they are
> > supposed to be multiplexed)?
>
> Actually, there's only ever one online log (OK, maybe briefly two, whilst
> one's being checkpointed). The other 'online logs' have of course already
> been backed up. That's what ARCH does.
>
> > Yes, you can recover the database, but surely you lose the last few
> minutes
> > worth of updates?
> >
>
> Entirely true. But so what? That's not an argument for backing up the
> online logs, is it? It's rather an argument for multiplexing.
>
> Suppose you backup the online logs, against all Oracle's advice, RMAN's
> in-built capabilities, and my repeated entreaties not to. That was last
> night. How is restoring a 9-hour old 'online log' going to help you *not*
> lose the last transactions that were contained in the real-life online
logs?
>
> If you lose your online logs, you have absolutely no alternative but to do
a
> 'recover until cancel', cancel when it prompts you for what you know to be
> the missing logs, and then open resetlogs. At which point you get your
> online logs back... but, yes, missing the last dollop of redo, and hence
> with some lost transactions.
>
> The *only* thing you can do to prevent that is multiplex.
>
> Backing up the online logs doesn't help at all.
>
> Cheers
> HJR
>
>
>
> > Regards,
> > Paul
> >
> >
> >
>
>

Howard,

Sorry, I didn't phrase the question properly. I meant to ask: 'What happens if you lose all the (multiplexed) members of the current online redo log'?

But you have already answered the question.

Thanks,
Paul Received on Sat Dec 21 2002 - 13:02:26 CST