Re: Duplicating from copy of a standby with standby controlfile

From: Don Seiler <>
Date: Mon, 10 Feb 2014 16:53:46 -0600
Message-ID: <>

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 <> 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 (<//>)
> 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 <> wrote:
>> Version is 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

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

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