I also appreciate Mr. Railbeck feedback. We have been using an all disk primary backup pool for over 4 years now and recently switch our copy pool to all disk NAS located at a remote site for DR. While Mr. Railbeck's comments may be correct in theory, for me in practice they don't hold up. For instance he said "This (no reclamation for random access storage pools) can cause inefficient utilization of the disk space over time" , my experience shows random access is still more efficient use of space than sequential due to the fact that I set my reclaim threshold for sequential media at 50%. For me setting the reclaim threshold higher is not worth the additional overhead.
Also of note is Mr. Rialbeck's statement "We have not done a lot of testing on this, so this can not be taken as a definitive statement". I suggest anyone interested in an all disk storage pool environment to test it for themselves. Considering TCO, that is, dirt cheap ATA's drives, lightening speed restores, and an incredibility simple DR solution, an all disk storage pool environment has been a real winner with us. It's made me happy, the users happy, and most importantly management happy. Thanks, john underdown SYNOVUS Phone:706-644-7592 -----Original Message----- Date: Mon, 9 Jun 2003 17:04:07 -0400 From: "Talafous, John G." <[EMAIL PROTECTED]> Subject: Re: anyone using ATA disk systems Mr. Raibeck, I appreciate your feedback and, being involved in IT for some 30 years, I understand the technical challenges involved. That is why I posted the question. With the falling cost of disk architecture, a disk to disk backup alternative seems to be coming close to rivaling disk to tape as a backup alternative. Especially when dealing with some of the more sophisticated tape solutions that involve the mainframe/zArchitecture. If I size my TSM solution such that I can recover 'x' number of application servers in a given number of hours, then I will require a certain number of tape drives based on the data transfer rate of each tape drive. Hence, any recovery process in DR mode is limited to the number of tape drives available. Ouch!!! With disk to disk, my limitation is the TSM server and the network. Add to the mix the fact that tape data transfer speeds are less than SCSI and/or ATA data transfer speeds and the thought is that with capacity of disk architectures increasing rapidly and the price currently lower than tape, it makes sense to back up everything to disk!!! Faster and lower cost! So, I/we would appreciate IBM Tivoli's support of this concept. With all the pressure on budgets and all these jobs NAFTAing, I MUST arrive at the best solution! Thanks for your consideration. John G. Talafous IS Technical Principal The Timken Company Global Software Support P.O. Box 6927 Data Management 1835 Dueber Ave. S.W. Phone: (330)-471-3390 Canton, Ohio USA 44706-0927 Fax : (330)-471-4034 [EMAIL PROTECTED] http://www.timken.com -----Original Message----- From: Andrew Raibeck [mailto:[EMAIL PROTECTED] Sent: Monday, June 09, 2003 1:33 PM To: [EMAIL PROTECTED] Subject: Re: anyone using ATA disk systems Addendum: I as I said earlier, we continue to study the matter. Possible outcomes include enhancements that will enable TSM to function better in an all disk storage pool environment, although we make no commitments at this time. Regards, Andy Andy Raibeck IBM Software Group Tivoli Storage Manager Client Development Internal Notes e-mail: Andrew Raibeck/Tucson/[EMAIL PROTECTED] Internet e-mail: [EMAIL PROTECTED] The only dumb question is the one that goes unasked. The command line is your friend. "Good enough" is the enemy of excellence.
