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Home -> Community -> Usenet -> c.d.o.server -> Re: Shutdown Abort - Not a Good Idea, Right?
Mohammed
A shutdown abort is used when you want to kick users off as quickly as possible. Say for example, you've just accidentatlly dropped some tables. You will want to do an incomplete recovery, so to minimize the data loss you do a shutdown abort to stop users entering data. What actually happens with the abort is that the instance is shut down (i.e. the background processes and the SGA are removed), while the database files themselves remain open.
A shutdown immediate is a cleaner approach. It disconnects any connected users, rolls back their uncommitted transactions, frees any locks, then shuts down both the database and the instance. As a result, the database files are not open. It will normally be slower than a shutdown abort however.
For completeness, a shutdown normal waits for everyone to log off, then closes the database and the instance.
With all that as background, what is the right approach in your situation? DBA's used to (and some still do) use the mechanism in your script - shutdown abort to kick off users, then startup followed by shutdown normal to clean up the database files. The reason? An old documentation bug. The Oracle manuals at one stage stated that a shutdown immediate (which in effect is doing the same thing as your current three step process) would not leave the database in a clean state and that recovery would be required on next startup. I believe (someone please correct me if you know better) that this documentation bug has been fixed.
The other reason for using the three step process is that sometimes on some platforms the shutdown immediate would hang. There doesn't seem to be any consistency in the reports I've seen on this newsgroup, but others may be able to comment on specific OS's, versions etc.
The short answer to your question is that you should be able to safely remove the three step process and replace it with a shutdown immediate.
HTH. Pete
M. Bhatti wrote:
> I just recently noticed that, before doing cold backups, our db
> instances (Oracle 7.3.2/8.0.5, Sun Solaris 2.5.1) are shutdown aborted
> than brought up and shutdown normal, so that the cold backup can be
> started immediately after the shutdown normal.
>
> Question is, I thought shutdown abort should not be used except in
> extreme conditions ie when a db instance
> cannot be shutdown normal/immediate.
>
> So, I assume that:
> This is bad idea right (shutdown abort)?
> What can happen to the db?
>
> Thanks for any input.
>
> mkb
--
Regards
Pete
Peter Sharman Email: psharman_at_us.oracle.com WISE Course Development Manager Phone: +1.650.607.0109 (int'l) Worldwide Internal Services Education (650)607 0109 (local)San Francisco
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Received on Wed Apr 21 1999 - 11:16:15 CDT
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