If you have a mirror (even on the same disk) and your tsm goes down dirty you have much better chances that your database will not get corrupted. TSM writes first to one db volume, when this commit is succesfull it writes to the mirrored volume. When the tsm server crashes only one volume will get corrupted. (the one it was writing to) If you only have one volume the above is not possible, and your db will get corrupted. This means you will have to restore your DB.
Same goes for your log volumes.
regards
Paul Fielding wrote:
I don't see the value in mirroring the db and logs if they're placed on Shark disk. The purpose of TSM's mirroring is to provide disk redundancy in case of disk failure. However, the Shark provides it for you. Why add the extra overhead of software mirroring when the hardware does a valiant job in the background. The Quck Start recommendation doesn't take into account that your disk is already protected...
regards,
Paul
----- Original Message ----- From: "Jones, Eric J" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Wednesday, April 06, 2005 2:56 PM Subject: [ADSM-L] Question on SETUP
Good Afternoon. I was asked to setup a new TSM server 5.2.2 on a AIX 5.2 server. My question has to do with setting up the DB, LOG and DISKPOOL. On our current servers which run the same O/S and TSM version the DB, LOG and DISKPOOL are mirrored. On the new system I'm setting up these are all going to reside on a IBM SAN(SHARK) which is all RAID. Is there any reason to mirror them since the mirror would be on the same set of drives(space was already allocated on a LUN)? I understand it's always good to mirror(protect DB, LOG, DISKPOOL) but in this case I'd have to mirror to the same set of disk since I was only allocated a set of space to work. In the TSM class it also recommended that you mirror for protection. I'm in the middle of reading the "Quick Start" for the second time and I see they recommend "Mirror your Database and recovery log for "Server and storage pool protection". I wanted to make sure there was not a performance issue or anything else.
Have a Great Day, Eric Jones
* [EMAIL PROTECTED] *: 607-751-4133
Cell : 607-972-7621
-- Otto Schakenbos System Administrator
TEL: +49-7151/502 8468 FAX: +49-7151/502 8489 MOBILE: +49-172/7102715 E-MAIL: [EMAIL PROTECTED]
Teleflex Holding GmbH Corporate IT Europe Fronackerstrasse 33-35 71332 Waiblingen GERMANY
