Re: Duplicating from copy of a standby with standby controlfile

From: Don Seiler <don_at_seiler.us>
Date: Mon, 10 Feb 2014 16:53:46 -0600
Message-ID: <CAHJZqBCTj=NnQ9TjiXzMMf6JR9Y60nTpcrfiNEKyM5sSu6LbLQ_at_mail.gmail.com>

Curious. When you say "backup the existing controlfile" do you mean the controlfile from your standby or a new copy/snapshot?

And yes I'd be interested in seeing what you have.

On Mon, Feb 10, 2014 at 4:29 PM, Mark Burgess < mark_at_burgess-consulting.com.au> wrote:

> We do this with a combination of ZFS snapshots and clones from the standby
> database - no backupsets as such.
>
> The method we have implemented to have the correct controlfile in place is:
>
> 1. Stop media recovery on the standby database.
> 2. Take the ZFS snapshot and clone of the relevant file systems.
> 3. Mount the snapshot database - this needs the control_files parameter
> pointing to the location of the clone file system.
> 4. Rename the redo logs - SQL script does this.
> 5. Rename the datafiles - we use RMAN to catalog the datafile copies and
> then do a switch to copy.
> 6. Backup the existing controlfile and restore the controlfile <-- this is
> the important bit as it gives you a normal control file and not a standby
> controlfile.
> 7. Recover until cancel on the database using backup controlfile.
> 8. Open database with reset logs.
>
> I have this scripted up - the database piece is independent of the method
> used to provide the copy of the datafiles.
>
> I can send through the scripts if you are interested.
>
> Regards,
>
> Mark Burgess
>
>
>
>
> On 11 February 2014 at 8:39:13 am, Don Seiler (don_at_seiler.us<//don_at_seiler.us>)
> wrote:
>
> OK I've played a little more with the duplicate steps (using target-less
> duplication with BACKUP LOCATION specification) and so far it seems to only
> work with backups, not with datafile copies. I'd like to keep using the
> datafile copy method as it saves time, and our database is nearly 25Tb.
> Creating a "backup as copy" of the database and remounting the disks saves
> us from having to backup and then restore the datafiles which would take
> far too much time.
>
> Like I said, this method works great but so far requires a primary
> controlfile. It's really only an extra step when we do the refresh from the
> standby side but I'd like to see if we can do it without having to do that
> step, just to simplify and script as much as possible.
>
>
> On Sat, Feb 8, 2014 at 1:46 PM, Don Seiler <don_at_seiler.us> wrote:
>
>> Version is 11.2.0.3. I'll explore the duplicate options. Anyone done it
>> with data file copies target than backup set? I'd rather not do active our
>> require connection to primary or standby other than the initial backup as
>> copy.
>>
>

-- 
Don Seiler
http://www.seiler.us

--
http://www.freelists.org/webpage/oracle-l

Received on Mon Feb 10 2014 - 23:53:46 CET