Re: How do I backup to /dev/null?

John,

To take the tape drives out of the equation, you can create a file device
class and back up to a disk directory.

To understand where the time is spent on backups, however, you can turn on
tracing to see the breakdown of operations.

I'd still like to know the direct answer to your question, however.  There
are times I'd like to be able to run a test backup to the null device.  It's
a bit dangerous - you might forget and leave your backup directed there . .
.

Bill Smoldt    SSSI
Storage Solutions Specialists, Inc.


 -----Original Message-----
From:   ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU]  On Behalf 
Of
John Schneider
Sent:   Monday, March 06, 2000 10:42 AM
To:     ADSM-L AT VM.MARIST DOT EDU
Subject:        How do I backup to /dev/null?

Greetings,

Is it possible to configure TSM to backup to /dev/null under AIX?  The
reason I want to do this is I want to remove the performance of the tape
drive units from the rest of the TSM performance.  If the backup can go
directly to /dev/null, then the tape drive speed isn't slowing things
down.

The speed of the database backup software, SQLBackTrack and Oracle,
drive contention, load on the system, etc. all are part of the
equation.  I have a customer who is considering upgrading to faster tape
technology to speed up their backups, but how do we know for sure if
that is where the bottle neck is?  Typically the network would be, but
in this case the server and the client are on the same machine.

I figure that if we could backup to /dev/null, then we can see what the
raw throughput of the rest of pipeline is, and that way we know if
faster tapes will help.

Any suggestions, including a completely better way to solve this
problem, are appreciated.

John Schneider

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* John D. Schneider   Email: jdschn AT attglobal DOT net * Phone: 636-349-4556
* Lowery Systems, Inc.
* 1329 Horan                  Disclaimer: Opinions expressed here are
* Fenton, MO 63026                   mine and mine alone.
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