Re: RMAN v Control Files

Hi!

Why are you doing two incremental backups per day? Is it because of very short allowed recovery time? What's the max time to recover requirement for your systems?

Why I'm asking this - I've sometimes seen that people with unix/windows (non-oracle) background do not realize that Oracle archivelogging feature, if properly configured, allows you to recover your database to any point in time (in past or present ;)

You have fairly small databases, is they aren't extreme 24x7 systems, you could wery well get away with nightly full backups and continous archivelog shipping to another server/disk/tape.

Tanel.

"Gary Mandaracas" <garym_at_singnet.com.sg> wrote in message news:b2nvo7$jlp$1_at_reader01.singnet.com.sg...
> Thanks for your feedback.
>
> Your right, Data Protector is just HP's backup software which integrates
> with Oracle and other software.
>
> We are currently on 8i, I don't know if your comment on the catalogue
> database no longer being required still applies.
>
> I'm not sure what constitutes a complicated backup strategy but we have
four
> databases on 8i and take two incremental backups during the day plus a
full
> online backup at night - each database is around 30Gb.
>
> Cheers
>
> Gary
>
> "Howard J. Rogers" <howardjr2000_at_yahoo.com.au> wrote in message
> news:pan.2003.02.15.22.39.30.233848_at_yahoo.com.au...
> > On Sat, 15 Feb 2003 22:46:29 +0800, Gary Mandaracas wrote:
> >
> > > Can anyone advise,
> > >
> > > We have installed HP's Data Protector to backup our Oracle databses
and
> > > other systems in two of our sites and been given different advise by
> > > consultants working on each installation.
> > >
> > > For Data Protector you can configure the backup to integrate with RMAN
> or
> > > make use of Control files. In the first install we where advised to
> > > configure RMAN prior to the consultant coming in to install and set-up
> the
> > > backup software, however in a more recent install at another site the
> > > consultant advised us to make use of the Control files.
> > >
> > > Is he cutting corners to get the job done or does it really make no
> > > difference? What are the pros and cons of each approach?
> > >
> > > Any advice would be appreciated.
> > >
> > > Gary
> >
> > It's not entirely clear what you are talking about, because I don't know
> > the specific product you mention but I *think* you are
> > saying that one consultant advised the use of a Catalog Database for
RMAN
> > to use as its repository, and another advised not to bother with a
Catalog
> > Database at all, but get RMAN to store its repository information in the
> > Control Files of the target database itself. (I'm assuming that this
Data
> > Protector is just an HP fancy front-end for RMAN. Ignore the rest of
this
> > post if that's not the case).
> >
> > If that is a fair summary of what you've been advised, then my view is
> > that it's the one recommending the use of a Catalog Database that needs
to
> > get up to speed. There is little need for one in 9i, unless your backup
> > strategy is complex, your backup volumes are high, or you have some
other
> > weird backup requirement.
> >
> > However, it does mean that RMAN will be storing stuff in your control
> > files. Firstly, that makes the control files get bigger -though not by
> > much -maybe 60MB or so. Secondly, you need to make sure that you never,
> > ever lose all copies of your control files (multiplexing is easy, ought
to
> > be compulsory, and does the job nicely... and I mean multiplexing, not
> > hardware mirroring, though you can do that as well). Having said that,
if
> > disaster strikes and you *do* lose all copies of your control files,
then
> > recovery is still possible, provided you make sure that you configure
> > RMAN's automatic backup of control files feature (which mysteriously
> > and very stupidly defaults to being off!). Thirdly, make sure the
control
> > file retains records long enough to cope with 'odd' recoveries: the
> > default is for the control file entries to begin to be over-written
after
> > 7 days, but that would potentially mean it was impossible to perform an
> > unusual recovery from a backup taken 8 days ago. Use the init.ora/spfile
> > parameter CONTROLFILE_RECORD_KEEP_TIME to bump up the number of days to
> > something appropriate for you.
> >
> > There was a 'fourthly', but I've forgotten what it was!
> >
> > So I'll leave it there, particularly since none of this might actually
> > apply to this HP product.
> >
> > Regards
> > HJR
> >
>
>
Received on Sun Feb 16 2003 - 08:13:56 CST