How does your database run?  How many clients does one database backup?  How
many files does it track?

        I am not sure of a good baseline to gauge database speed, but I know
our Informix database a lot faster on SAN attached storage than on local
disk arrays.  If anyone has ideas, I would like to determine if SAN disk can
provide the same database boost for the ADSM database.
Jeff Bach
Home Office Open Systems Engineering
Wal-Mart Stores, Inc.

WAL-MART CONFIDENTIAL


        -----Original Message-----
        From:   Joel Fuhrman [SMTP:joelf AT CAC.WASHINGTON DOT EDU]
        Sent:   Tuesday, June 12, 2001 9:28 PM
        To:     ADSM-L AT VM.MARIST DOT EDU
        Subject:        Re: tsm mirroring vs pprc

        Dave, what the level of the TSM server that caused this problem?

        On Tue, 12 Jun 2001, Frost, Dave wrote:

        > Richard,
        >
        > "BTDTGTTS"
        >
        > We are running tsm using san attached emc for all disk storage.
On initial
        > setup of the emc, we decided to stop using log/db mirroring, and
use the emc
        > mirroring instead.
        >
        > Soon afterwards, we had 2 instances where we could not restart the
server.
        > Both times the server failed to restart because of an
inconsistency in the
        > db log file.  The emc mirroring had faithfully replicated the
inconsistency,
        > of course.  In each case, the database had to be restored.  Given
a 35 GB
        > database, a restore can take about 2.5 hours.
        >
        > IBM said that they "strongly recommend tsm mirroring", preferably
with
        > verification.
        >
        > So do we, now.
        >
        > regards
        >
        > -=Dave=-
        >
        > -----Original Message-----
        > From: Richard Bates [mailto:Richard_Bates AT UK.IBM DOT COM]
        > Sent: 08 June 2001 12:25
        > To: ADSM-L AT VM.MARIST DOT EDU
        > Subject: tsm mirroring vs pprc
        >
        >
        > Folks,
        >
        > Customer site: TSM running on AIX.  2 x IBM Enterprise Storage
Server, one
        > per data centre. SAN connecting it all together.
        >
        > Problem: I've seen and read all the posts about TSM mirroring vs
AIX
        > mirroring vs RAID mirroring.  I understand the probem with partial
page
        > writes and prefer TSM mirroring.  We had planned to implement TSM
mirroring
        > with a copy of the database and recovery log on IBM ESS in both of
the data
        > centres.
        >
        > However company strategy says that *all* mirroring must be done
via PPRC.
        > Does anyone have any experience with PPRC?  Can it cope with
partial page
        > writes?  Am I safer to use TSM mirroring?
        >
        > Regards
        > Richard.
        >
        > Richard Bates
        > Storage Specialist
        > ITS - SB - Enterprise Consultancy Services
        > ==========================================
        > Voice :  00 44  (0) 1926 462298  (HICOM : 662298)  (MOBEX :
270798)
        > richard_bates AT uk.ibm DOT com
        > richard_bates AT uk.ibm DOT com
        >
        >
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