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Wednesday, October 24, 2007
We recently acquired a Spectra Logic T950 library for one of our data centers and I thought I'd let you all know how it's been performing. Since I was with IBM previously my only experience was with STK's (which we were trying to push out the customers door ASAP) and IBM hardware. I can say I was no fan of the STK L700 and being an IBM'er at the time I touted the 3584 and 3494's like they walked on water (they don't). We frequently had to have maintenance on our IBM libraries. Was it due to the fact we were collocating over 2500 clients and mounts were through the roof? Probably!
The data center I worked at with IBM had a secondary library room that housed the 8 libraries (some were for mainframes) and tape shelves. The room was running out of floor space to accommodate another library or expansions to existing ones. This is where SpectraLogic has IBM and the competition beat, hands down. A single T950 frame can house up to 24 drives and a max of 950 tapes with a frame H 78.77 in, W 30.63 in, D 43.21 in (H 200.1 cm, W 77.8 cm, D 109.8 cm). That's a little taller but less deep than an IBM TS3500 frame at 70.9"H x 30.8"W x 47.7"D (1800 mm x 782 mm x 1212 mm), with the IBM L frame handling a max of only 12 drives and 287 tapes.
How does SpectraLogic get such great density? They go vertical with a twist. SpectraLogic libraries use "TeraPacks" that are 10 tape chassis that load the tapes so the barcode are vertical not horizontal like IBM and most other libraries. When the library needs a tape its robot removes the TeraPack and then the gripper mechanism grabs the tape. I can hardly tell if it adds more than a second or two to the mount time, but even if it does the density gain negates the ever so slightly increased mount time.
I could go on an on and mention every little thing that I like about this library, but one of the coolest features is the ability to add SATA RXT portable RAID media, making the T950 VTL capable. The RXT media (which stands for RAID eXchangeable TeraPack) fits in the SpectraLogic half inch tape drive openings and is composed of multiple SATA disks sealed in a enclosure capable of taking rugged handling with built in shock dampening technology. The TeraPacks range in size from 2TB to 1TB, but I'm sure you will see larger sizes in the very near future. The RXT media is compatible with all major backup applications and operating systems.
The final item that sealed the deal was of course price. This library came in at a great price point, lower than IBM and Sun by quite a bit. This, added up with all the other features/benefits it offers in expandability, made it a win/win. "So, how has it performed?" You ask. Well, so far it has performed above my expectations. I have shed my IBM favoritism and seen it for what it was "stubbornness". I would highly recommend considering SpectraLogic the next time you seek to buy new or refresh old equipment. They definitely have the features everyone is looking for available in their libraries, and with data center space at a premium you can count on the T950 to give you the capacity you need in less space than competing libraries.
The mount time is a a lit more excessive than thought. Because of the TeraPack having to be removed, then the tape grabbed and placed in the drive, then the terapack replaced; the mount times are quite a bit longer when you have a VERY busy queue. I think SpectraLogic needs to speed this process up somehow. I must say if they can speed it up the overall library density is great. It would be cool if there was some way they could utilize a tool that grouped all scratch together and tapes that are most frequently mounted. Almost like a tape slot reclamation. It might speed things along when say 5 systems are all waiting for scratch. I need to research this a little more. I'll see if I can get feedback from SpectraLogic.