In <bitnet.adsm-l%0012900001032415000004*@MHS>, jlawson AT itthartford DOT com
(Jerry Lawson) writes:
>Date: February 20, 1996 Time: 09:54
>From: Jerry Lawson
> ITT Hartford Insurance Group
> (203) 547-2960 jlawson AT itthartford DOT com
>-----------------------------------------------------------------------------
>I thought we knew what was going on with this question, but then we read the
>manuals....... :-)
>
>We have been mirroring our DB, but since the DB resides on an STK Iceberg, we
>have decided that the benefits of mirroring are outweighed by the cost of the
>extra DASD required. So..... we decided to remove the mirroring. We read
>through the Admin GUIDE on reducing the DB, and also in Admin reference, and
>in that volume I found the following statement:
>
> "You cannot delete the last synchronized volume in a copy set unless the
>information on the volume can be moved by ADSM to other synchronized volumes
>in the database"
>
>The Glossary definition of Synchronized Copy Status helps to add to our
>confusion. As I read this, when a DB volume is mirrored (a copy is added),
>then it becomes Synchronized. (??) If that is true, then based on the quote
>above, is it even possible to delete the mirror once it has been added? Some
>of the confusion depends on the definition of a mirror - If i have 2 DB
>volumes (DB1 and DB2), and two mirrors (DBA and DBB), is the synchronization
>done between pairs of volumes (DB1 and DBA)? The manuals indicate that the
>mirror can be larger than the original DB - does this add to the problem.
>
>By the way, our mirror is only 1 copy per volume, not 2.
>
>Has anyone actually deleted their mirror once they started it?
>
>In a related (somewhat) question, the Admin GUIDE has a good description of
>how to remove DB Volumes, with examples on how to reduce and delete a volume.
>One question that came up, though, was found in an examination of the syntax
>of the commands - The Vary command mentions the DB; The GUI also has a button
>for Vary On/Off. Knowing how the rest of MVS works, shouldn't the DB Volumes
>be varied offline before a delete is done?
>
>*****************************************************************************
>Jerry Lawson
>ITT Hartford Insurance Group
>jlawson AT itthartford DOT com
>
>QUIT
I used to have mirrors when the database was on 3380-k, but I didn't
bother to receate them when it was moved to an Iceberg. To answer your
questions, look in the V2 Admin guide at figure 15 on page 80. With this
as an example, issue 'delete dbvolume <datasetname>' for all the
'Volume Name (copy 2)' volumes. This will remove the database mirroring
in ADSM. Then do the TSO 'delete' command to delete the 'copy 2' files.
ADSM does not delete them.
You don't need to do any reduce commands.
(I recommend practicing this on a test server to build confidence.)
Bill Colwell
C. S. Draper Lab
Email: BColwell AT draper DOT com
Voice: 617-258-1550
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