Quiescing the catalog and directory

Alan Smith

Quiescing the catalog and directory
The DB2 utility guide has the following advice on quiecing the catalog
and directory:

If a point-in-time recovery is planned for the catalog and directory, a
separate
QUIESCE control statement for DSNDB06.SYSCOPY is required after you
quiesce
the other catalog and directory table spaces. Recommendation: Recover
all
catalog and directory objects to the current state.

Ignoring SYSUTILX, this means that you end up with two quiesce points
for the catalog and directory tablespaces. So if you want to recover to
a point-in-time, which point would you use? If you use the first one,
there is a possibility that there was an open unit of work on SYSCOPY
at that time. If you use the second one, there is a possibility of
uncommitted work on one of the other tablespaces.
I would have thought that it would be better to use one quiesce point -
if you recover to that, then everything would be in line and there
wouldn't be any uncommitted UORs.

Alan Smith

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Michael Ebert

Re: Quiescing the catalog and directory
(in response to Alan Smith)
I think the point is that if you quiesce SYSCOPY along with the other TSs,
and then recover to that PIT, then the QUIESCEs won't show up in SYSCOPY
because it it updated only after the successful quiesce.
If you plan to do a PIT recovery of the Cat/Dir, then you should be very
sure that there is no other update activity against the Cat/Dir (in which
case it does not matter which RBA you use, apart from the mentioned
difference). That is, no DDL and no running utilities (apart from your
QUIESCE). Otherwise you're inviting serious trouble anyway.

Dr. Michael Ebert
DB2 Database Administrator
aMaDEUS Data Processing
Erding / Munich, Germany




From: Alan Smith <[login to unmask email]>@IDUGDB2-L.ORG on 31-12-2004
08:05 GMT

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Subjec [DB2-L] Quiescing the catalog and
t: directory








The DB2 utility guide has the following advice on quiecing the catalog
and directory:

If a point-in-time recovery is planned for the catalog and directory, a
separate
QUIESCE control statement for DSNDB06.SYSCOPY is required after you
quiesce
the other catalog and directory table spaces. Recommendation: Recover
all
catalog and directory objects to the current state.

Ignoring SYSUTILX, this means that you end up with two quiesce points
for the catalog and directory tablespaces. So if you want to recover to
a point-in-time, which point would you use? If you use the first one,
there is a possibility that there was an open unit of work on SYSCOPY
at that time. If you use the second one, there is a possibility of
uncommitted work on one of the other tablespaces.
I would have thought that it would be better to use one quiesce point -
if you recover to that, then everything would be in line and there
wouldn't be any uncommitted UORs.

Alan Smith

---------------------------------------------------------------------------------
Welcome to the IDUG DB2-L list. To unsubscribe, go to the archives and home page at http://www.idugdb2-l.org/archives/db2-l.html. From that page select "Join or Leave the list". The IDUG DB2-L FAQ is at http://www.idugdb2-l.org. The IDUG List Admins can be reached at [login to unmask email] Find out the latest on IDUG conferences at http://conferences.idug.org/index.cfm