| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
 |
 | |||
| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
|
| |||
Home -> Community -> Mailing Lists -> Oracle-L -> RE: Database Down
Laura
Document it to even those you CAN'T think of... just to try to CYA! I speak from experience!
April Wells
Oracle DBA
Corporate Systems
Amarillo Tx
-----Original Message-----
Sent: Wednesday, May 23, 2001 10:27 AM
To: Multiple recipients of list ORACLE-L
Paul you leave me NOTHING to add to this. :)
Laura..... I would do exactly what Paul said, and include what you thought to do (which is backup the good disks before you do anything else).
First rule of recovery: ALWAYS have a way to start all over again if you mess up.
After that, follow Paul's list :)
Once that is done, take a deep breath, then go find out who you have to stomp on to get the backup logs reviewed AS SOON AS THEY COMPLETE. (You might want to automate something that checks for errors and pages you). Find
out why no one knew there was a problem with the backup and why it waited until you came in.
Yell. Scream. And DOCUMENT what went wrong... to everyone you can think of.
Rachel
>From: Paul Drake <paled_at_home.com>
>Reply-To: ORACLE-L_at_fatcity.com
>To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
>Subject: Re: Database Down
>Date: Wed, 23 May 2001 00:00:23 -0800
>
> > "Burton, Laura L." wrote:
> >
> > I have an Oracle 8.0.5 database residing on a Windows NT operating
> > system which uses Raid5. The 'almost never' has happened; two disks
> > have gone bad at the same time. As fate would have it the 'complete'
> > physical backup performed the day before the disks crashed (Friday,
> > May 18) cancelled. Of course this happened on Saturday on a weekend
> > in which I was out of town and did not get back in until late this
> > afternoon.
> >
> > My system admin said he restored the drives on the bad disks from a
> > physical backup created the previous Friday (May 11) and then restored
> > the differential backup from this past Thursday (May 17). The Archive
> > files were also on one of the disk that went bad. I have looked at
> > the alert log and the hot backup executed on the Thursday prior to the
> > Saturday crash completed successfully. Something that does not seem
> > right, and I'll talk with my system admin tomorrow, is that when I
> > looked at the datafiles and archive logs he restored they were all
> > dated May 11, the date of the complete backup. If he applied the
> > differential as he said, does this not add the archive logs written
> > from May 11 through the May 17 differential backup? According to the
> > alert log it looks like I am missing approximately 438 logs.
> >
> > I thought I would have to restore all datafiles and archive logs from
> > the physical backup so that they would be in sync, and then 'recover'
> > the database using the hot backup. This would only incur minimum data
> > loss since Saturday is a non-work day for most employees. After
> > reading the Backup and Recovery manual it looks like all I have to do
> > is 'recover' the database using the hot backup. Wouldn't it matter
> > that the datafiles would not currently be in sync since the datafiles
> > on the disk which did not crash were ok and not restored? Since the
> > hot backup would restore all the datafiles I would think it wouldn't
> > matter. Correct??
> >
> > I would appreciate some second and third opinions. This is my first
> > 'live' recovery and I want to make sure as much as possible that I do
> > what will have the least impact on data loss. It goes without saying,
> > but I will have a complete backup of the 'good' disks before I tackle
> > this beast.
> >
> > Thank you in advance,
> > Laura
>
>0. caffeine.
>
>1. (you already know this) your latest archived redo log is what you
>will be able to recover the database to - nothing further. I assume
>that a budget for duplexed archived redo logs will be forthcoming.
>Network Attached Storage is possibly an even better solution - with
>scheduled jobs to propagate archived logs to the NAS box.
>
>2. You *will* be performing incomplete recovery. Recover until cancel,
>preferably with a backup controlfile.
> Did you create a backup controlfile as part of the hot backup on May
>11th? Restore with that controlfile.
>
>3. After the recovery is completed (you've opened RESETLOGS) close the
>database and get a *full* cold backup. Fight the urge to *get the
>database open* when you don't have anything to intiate your next
>recovery from. You don't want to have to repeat this entire processes
>*ever* again.
>
>4. Possibly, you want to have the SysAdmin restore the thursday night
>archived redo logs (17th) to a different folder than the previous backup
>set (11th). This may be the reason why the later set of archived
>redologs is not appearing.
>
>5. If you have more recent copies of datafiles than the May 11th backup
>set - move them to a different directory - and restore the entire hot
>backup set. Recovery will attempt to recover all datafiles to be in-sync
>at a specific SCN#. To have some datafiles ahead of that SCN could cause
>more problems. If you were attempting complete recovery - I would
>recommend otherwise.
>If you force the database open in an inconsistent manner, you'll have to
>export and rebuild (your last option - next to the data unloader).
>
>From the Oracle 8i Backup and Recovery Handbook
>pg 263
>
>"Regardless of the method used, the fundemental concept of recovery is
>very straightforward: Before opening the database, all data files must
>be recovered to the exact same point in time and not have any changes in
>the future from this point."
>
>As Rachel C. would say - Don't Panic!
>
>Best of luck,
>
>Paul
>--
>Please see the official ORACLE-L FAQ: http://www.orafaq.com
>--
>Author: Paul Drake
> INET: paled_at_home.com
>
>Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
>San Diego, California -- Public Internet access / Mailing Lists
>--------------------------------------------------------------------
>To REMOVE yourself from this mailing list, send an E-Mail message
>to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
>the message BODY, include a line containing: UNSUB ORACLE-L
>(or the name of mailing list you want to be removed from). You may
>also send the HELP command for other information (like subscribing).
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Rachel Carmichael INET: carmichr_at_hotmail.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). The information contained in this e-mail is strictly confidential and for the intended use of the addressee only; it may also be legally privileged and/or price sensitive. Notice is hereby given that any disclosure, use or copying of the information by anyone other than the intended recipient is prohibited and may be illegal. If you have received this message in error, please notify the sender immediately by return e-mail. Corporate Systems, Inc. has taken every reasonable precaution to ensure that any attachment to this e-mail has been swept for viruses. We accept no liability for any damage sustained as a result of software viruses and advise you carry out your own virus checks before opening any attachment. -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: April Wells INET: awells_at_csedge.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Wed May 23 2001 - 14:44:09 CDT
 |
 |