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Re: [Spam Bayes=90,69] Inheriting a "interesting" recovery process

From: Mogens Nørrgaard <>
Date: Fri, 04 Aug 2006 02:43:16 +0200
Message-ID: <>

First of all, I'd appreciate if you could provide us with your real name instead of some anonymous "STV"? I'm not sure why you'd want to be anonymous on a list where you want to get qualified and quick help from experts?

Second, you might as well disable your archiving. It doesn't work together with Export. So, yes, you stand to lose everything between two exports.

EXP and read consistency? That's easy. Yes. You can see it most easily with an "exp help=y" command. Since you already have the "CONSISTENT=Y" enabled, you're OK.

Drop the COMPRESS=Y thing, by the way. It's no good.


stv wrote:

> Greetings all,
> Summary
> =======
> I'm a newbie Oracle DBA in a new job [non-profit in a small town, life
> is like that sometimes ;-) ]. I'm busting my butt reading up on
> everything I can, but there is one issue that I want to understand
> immediately: RECOVERY. Right now, we are covered only by a nightly
> export using the EXP utility. Archived redo logs exist, but are not
> backed up.
> Exactly how much data do we stand to lose? My guess is anything that
> happened after the export (i.e. the redo logs don't help much as
> things stand), but I'm not sure of that.
> Does EXP have read consistency like a normal select? Or will there be
> some gray areas in the dump file if open transactions existed at the
> time of export?
> Details
> ======
> We are running Oracle 64bit on Solaris 8. However, the
> database has evolved since 1993 (starting, I believe, with Oracle
> 7.?), living through several front-end applications. There was one DBA
> for most of those years, self-taught, and one short-term guy before me
> (he lasted less than a year).
> The nightly dump file is copied to an offsite machine, a local machine
> and, once a week, tape. There is only one copy of the archived redo
> logs (on a separate disk from the datafiles). These logs are not
> copied off the production machine at any time. The control files
> appear to be saved on a variety of disks, but are not copied off of
> the machine.
> As I understand things, this is odd. Having archived logs is a Very
> Good Thing, but I read everything to say they are intended to be used
> with an official hot backup (i.e. ALTER TABLESPACE xyz BEGIN BACKUP).
> Given that we are already in archived log mode, I think I have a basic
> understanding of where things need to go, using the proper hot backup
> commands, having more copies of the redo logs & such. But that's
> another post.
> Right now I'd like to make sure the Powers That Be understand where we
> are and why I'm gonna be busy on something they perhaps thought was
> solid. I intend to start testing the recovery process ASAP ... is it
> even worth testing the current system?
> Configurations
> ===========
> The export command:
> exp USERID=system/secret BUFFER=30720 \
> Some relevant init.ora settings:
> log_archive_dest=/u07/oradata/SID/archive
> log_archive_format=arch_%t_%s.arc
> log_archive_start=TRUE
> control_files=("/u02/oradata/SID/control01.ctl",
> "/u03/oradata/SID/control02.ctl", "/u04/oradata/SID/control03.ctl")
> Resources
> =========
> Saw this 2004 thread:
> Scanned stuff here:
> --

Received on Thu Aug 03 2006 - 19:43:16 CDT

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