Re: shutdown immediate or abort for cold-backup?

"Leonard F Clark" <lfc_at_zoom.co.uk> wrote in message news:3b7e520c.5005337_at_192.168.0.1...
> I'm reluctant to get involved in what looks like becoming a minor
> flame war but I hope my comments may add value.
>
> I thought it was standard practice (and is certainly advice from
> Oracle) to do the following for batch shutdowns:
>
> 1. Shutdown abort
> 2. Startup normal (probably best in restricted mode)
> 3. Shutdown normal
>

This is not the case! Shutdown abort always presents risk of data loss and database corruption. The Oracle server is extremely adept at recovering from crashes (which the shutdown abort is), but there is always risk.

This is from the Oracle web site:

To guarantee that a database's datafiles are consistent, shut down the database with the NORMAL, IMMEDIATE, or TRANSACTIONAL options before making a whole database backup. Never perform a whole database backup after an instance failure or after the database is shut down using a SHUTDOWN ABORT statement unless your database is in ARCHIVELOG mode.

To make a consistent whole database backup:

  1.. If the database is open, use SQL*Plus to shut down the database with the NORMAL, IMMEDIATE, or TRANSACTIONAL options:

SHUTDOWN NORMAL
SHUTDOWN IMMEDIATE
SHUTDOWN TRANSACTIONAL   Do not make a whole database backup when the instance is aborted or stopped because of a failure. Reopen the database and shut it down cleanly first.

  2.. Use operating system commands or a backup utility to make backups of all datafiles and all control

The startup restrict, shutdown normal simply permits Oracle server to do any needed repairs (if it can), but there is not guarantee that there has been no loss of data. Elsewhere in this thread someone has described the danger of blocks and buffers not being completely written to disk before the shutdown abort. Received on Sat Aug 18 2001 - 23:42:21 CDT