Comments below
HJR
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Resources for Oracle: http://www.hjrdba.com
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"daniel" <test_at_test.com> wrote in message
news:a7deuk$417$1_at_newsg2.svr.pol.co.uk...
> as a rule of thumb u don't roll forward from a cold backup, (yes, yes I
know
> you can but lets not get into bad habits)....
>
That's simply not true, and it's not a bad habit either. Of course you can
roll forward from a cold backup. And taking cold backups is much easier
than the hot variety.
> you can use just hot backups no probs and can recover quicker from them
>
> pointers;
>
> have multiple ctl files spanning physical disks
> multiplex your online redo logs across physical disks
> aim to log switch every 15 mins
Dreadful advice. If you want performance, log switch every 24 hours, in the
dead of night, when no-one gives a damn about the huge amount of I/O the
associated checkpoint will induce. If you want Instance Recovery in ten
seconds, log switch every second or so. Somewhere in between those two
extremes will be a happy medium for *you*.
> every time you change the db structure "alter database backup controlfile
to
> trace"
Equally dodgy advice, I think. Backup to trace should be routine. Every
backup should include it.
> after the hot backup take a copy of the ctlfile and "archive log current"
> and make sure your archive redo logs are protected stream them off
somewhere
> else every 15 mins
Depends on your log switch rate, of course (see above!!)
> also when you take the hot backup keep a copy locally if enough space also
> stream to tape and if recovery time is an issue copy to some network
storage
>
Agreed. Keep as much on disk as possible.
Regards
HJR
> good luck
>
> daniel...
>
>
> "Dale DeRemer" <dderemer_at_agmc.org> wrote in message
> news:a7dcs8$q7u$1_at_malgudi.oar.net...
> We are new the the Oracle world. We want our ebusiness server to be 7x24.
> Never, ever down. Meaning... no cold backups. So, our question is this: If
> we use hot backups, (RMAN), and never take a cold backup, will we be able
to
> recover from any failure. Additionally, what is the impact, or difference
in
> recovery time for a system with no cold backups, vs. one with a cold
backup
> done once a week, or once a month?The DB is 75GB and will grow to about
> 100GB over the next year. It will be updated in batches from our
mainframe.
> Users will not update it. Thanks for your help.
>
>
>
>
Received on Fri Mar 22 2002 - 01:04:01 CST
