Re: recovery method

From: John Higgins <JH33378_at_deere.com>
Date: Fri, 11 Jun 1999 09:10:52 -0500
Message-ID: <376118EC.7DC80617_at_deere.com>

I could not tell from your description of your backup if you are really covered.

To recover your database using a hot backup you must have:

1) the control files
2) the data files
3) the log files created during the backup

It is point 3 that I am worried about.

If your backup procedure does the following, you are OK:

1) after the datafile backup, you switch logfiles
2) you wait until the just terminated log file is archived
3) you backup all archived log files (this now includes the log file that

was current at the start of the backup as well as the log file that was current at the end of the backup and all log files in between)

By having ALL the log files that were in use during the backup, you can restore the data files and recover (cancel after the last log file is applied).

Can't you buy just one more disk? If the archived logs are on a separate disk, you greatly reduce the risk of losing a day's work.

What about archiving straight to tape? You could switch the destination to disk during the backup and then switch back to tape.

by999_at_hotmail.com wrote:

> In article <z7D73.1550$CG.58953_at_typ31b.nn.bcandid.com>,
> "Van Messner" <vmessner_at_netaxis.com> wrote:
> > The customer doesn't care that much about this database and he's told
> you he
> > can lose a day's data. If you have a crash, just do a restore from
> the
> > previous night's tape. You are doing a cold backup every night,
> right?
>
> Thank you for your help. I can't do a cold backup every night. Although
> losing one day's data is acceptable, the database has to be on 7x24. So
> I do hot backup everyday. But in the case of disk crash, all I have is
> from previous day's tape, which are the tablespace datafile, control
> file, on-line redo logs and archived logs. I am wondering what is the
> proper recovery strategy provided I only have previous day's datafile,
> control file, on-line and archived logs (all these are from a hot
> backup). I read Oracle 7 documentation, but can't find a way that really
> fit into my case. Please help me!
>
> Thanks a lot.
>
> Brian
>
> >
> > Brian Yan <by2_at_gpu.srv.ualberta.ca> wrote in message
> > news:375DCC86.61FA_at_gpu.srv.ualberta.ca...
> > > Hi there, I just took over a very bad designed oracle database (7.1)
> on
> > > SCO unix box. There is only one physical disk. Everything (datafile,
> > > log, archived log, control file) is in one directory. Customer has
> no
> > > plan to upgrade the hard disk. The database is run under archivelog
> > > mode. It is O.K. to lose one day data. Currenly, we have all on-line
> > > datafile backup and archived log backed to tape every night. I am
> > > wondering in the case of disk failure, can I just copy all the
> datafile
> > > plus the archived logs to the same directory as before (assumed
> server
> > > directories have been restored to the image before crash)? then
> startup
> > > database, run the recover command? I am very new on oracle recovery.
> Any
> > > suggestion would be very much appreciated. Thank you in advance.
> > >
> > > Brian Yan
> > >
> >
> >
>
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Received on Fri Jun 11 1999 - 16:10:52 CEST