Re: Recovery practice

From: PHernandez <phph109_at_yahoo.es>
Date: 16 Apr 2005 10:54:37 -0700
Message-ID: <1113674077.247970.30820@g14g2000cwa.googlegroups.com>

Frank van Bortel wrote:
> PHernandez wrote:
> > Thanks a lot for your response!
> >
> > Sybrand Bakker wrote:
> >
> >>Comments embedded
> >>
> >
> > [...]
> >
> >>>If I instead had used
> >>>SQL> ALTER DATABASE BACKUP CONTROLFILE TO
> >
> > '/oracle/backup/control.bkp';
> >
> >>>could I have done
> >>>$ cp /oracle/backup/control.bkp
> >>>/u01/app/oracle/oradata/test/control01.ctl
> >>>and been saved?
> >>
> >>Yes, exactly. But then how likely is it you loose all copies of
your
> >>controlfile in a crash?
> >>Rman (when properly configured) autobackups the controlfile in this
> >>format.
> >
> >
> > I hade some idle time, and found note 60545.1 on metalink, which
helped
> > me getting the database up again. So it seems that the controlfile
was
> > in the backupset even though rman reports that controlfile
autobackup
> > is off...
> >
> > Is setting controlfile autobackup to on what you mean by properly
> > configured?
> >

>

> % rman target /
> RMAN> configure controlfile autobackup on;

>

> If you don't - any FULL backup has the control file (and spfile)
> in the same piece as the system tablespace. 9i R2 and above, not 8i!
> You can restore the controlfile, when you know the piece name, e.g.:
> RMAN> restore controlfile from '/o/oracle9/920/dbs/11ghmm8l_1_1';

Yup, this is clear to me now. I also understand that one needs to prepare a step by step recovery document for each system.

> >
> >
> >>>---
> >>>connect target;
> >>>run {
> >>> RECOVER COPY OF DATABASE WITH TAG "S";
> >>> BACKUP INCREMENTAL LEVEL 1
> >>> FOR RECOVER OF COPY WITH TAG "S"
> >>> DATABASE;
> >>>}
> >>
> >>This is a very strange and likely dangerous script as it makes an
> >>*incremental* backup (ie changed blocks only). You do have a level
0
> >>backup somewhere don't you? Otherwise you are toast.
> >
> >
> > Now, that scares me...
> >
> > from:
> >

http://download-west.oracle.com/docs/cd/B14117_01/server.101/b10735/bkup.htm#1034168
> > (might be wraped)
> >
> > "The BACKUP INCREMENTAL LEVEL 1... FOR RECOVER OF COPY WITH TAG...
> > command does not always create a level 1 incremental backup. If
there
> > is no incremental level 0 backup of an individual datafile to use
with
> > this level 1 backup, then executing this command creates a level 0
> > backup of the datafile with the specified tag."
> >
> > Am I missunderstanding the concept?
> >
> > ph
> >

>

> Why do you start with a recover, when you want a backup?

>

> RMAN> backup full database;
> would be sufficient.

Well, as I understand it, it's a recover of the copy (not the db) and BACKUP INCREMENTAL LEVEL 1 makes a full backup the first time, and then incremental backups. The only difference of that and allways making full backups is that incremental is faster. BTW, it's not my script, it's cut'n'pasted from the the doc mentioned above (almost, if my memory not fails me there was a syntax error and a typo in the example).

I am still aware of my limited Oracle knowledge, and since now two persons have told me that this script is strange, I'll just have to read more about the concepts available.

ph Received on Sat Apr 16 2005 - 12:54:37 CDT