We are also in the paranoid category. We use TSM to mirror both log and database, each of which are on RAID5 arrays (each array connected via separate HBAs). We have seen failures that have resulted in data corruption on RAID5 arrays (various vendors and causes), fortunately not on our TSM server, but on other servers. This type of failure is not protected by storage device mirroring or RAID protection, but should I think be protected by TSM mirroring. RAID5 provides nice protection against media failure, and we like the hot spare replacement that such arrays provide. It makes handling such failures very easy. And, while database backup and roll-forward log recovery can provide similar backup coverage for array failure, our database is so large that we feel a second copy is warranted. It provides us ride-through protection in the event of virtually any type of disk failure.
Our DB and LOG volumes are currently on IBM DS4000. ..Paul At 04:06 PM 9/1/2005, Tae Kim wrote:
Hello all, I wanted to know what your thoughts are on Mirroring DB or Log volumes that resides on a storage sub system (ESS, EMC, HITACHI). They are all supposed to be redundant enough to be up 99.9999% of the time with proper server configuration (multi path to multi fibre HBA) do you guys see the need the mirror your DB and Log volumes? Tae Kim McKinsey & Company 485 Madison Ave. New York, NY 10022 (212) 415-1724 +=========================================================+ This message may contain confidential and/or privileged information. If you are not the addressee or authorized to receive this for the addressee, you must not use, copy, disclose or take any action based on this message or any information herein. If you have received this message in error, please advise the sender immediately by reply e-mail and delete this message. Thank you for your cooperation. +=========================================================+
-- Paul Zarnowski Ph: 607-255-4757 Manager, Storage Systems Fx: 607-255-8521 719 Rhodes Hall, Ithaca, NY 14853-3801 Em: [EMAIL PROTECTED]
