Re: Incomplete Recovery

Norman Dunbar <ndunbar_at_lynxfinancialsystems.co.uk> wrote in message news:F43E6BAE5BB5D411A44C00805FBE740D465BBA_at_apps.lynx-fsc.co.uk...
> One thing I noticed from your post - you did a cold backup after a
> shutdown abort ?
> This is one way to totally screw the database - as far as I was taught
> on the Backup & Recovery course and from personal experience.
>
> You can only cold backup files from an instance that was closed using
> 'shutdown' and not any of the other variant - immediate or abort.
>

Not true -not entirely, anyway. Backing up cold after a shutdown abort simply means that the database, when restored in a noarchivelog scenario, will immediately need Instance Recovery. Provided the online redo logs were part of the cold backup (which is what is recommended on the Backup and Recovery course), and provided you restore the lot (ditto), you'll just have to wait longer than normal for the restore to result in a functioning database.

Things get more interesting if you take archives and do cold backups, and hence intend to restore single files and apply archives as your recovery strategy. Nevertheless, even then, provided you have all the redo from the time the relevant datafile was last checkpointed, you should get away with it. I agree, however, that you are pushing it by this stage.

> What I do when I need to bin some sessions is a shutdown abort, then
> startup restrict and shutdown again. Takes time, but at least I know the
> instance is in a reliable state when I take the backup.
>

I don't disagree, because one can never be too careful. But it's not strictly necessary. Combine sloppy backup habits, however, with excessively aggressive archive pruning techniques, and you are riding for a fall, big time.

Regards
HJR
> HTH.
>
> Regards, Norman.
>
> ------------------------------------------------------------------------
> --------
> Norman Dunbar EMail: NDunbar_at_LynxFinancialSystems.co.uk
> Database/Unix administrator Phone: 0113 289 6265
> Lynx Financial Systems Ltd. Fax: 0113 201 7265
> URL: http://www.LynxFinancialSystems.com
> ------------------------------------------------------------------------
> --------
>
> >> Database down, albeit after a shutdown abort, so the backup was cold.
>
Received on Mon Jan 29 2001 - 05:42:52 CST