Follow the Warranty
On the other hand, Marc Parpal Tamburini, a Hewlett-Packard product reliability engineer in Barcelona, Spain, suggested that false conclusions can be drawn by quick calculations and a lack of knowledge about statistics. He pointed to an interesting paper presented at ARS 2005 (International Applied Reliability Symposium) written by Sun Microsystems scientists David Trindade and Swami Nathan. In "Simple Plots for Monitoring Field Reliability," the researchers discuss the problems with MTBFstatistical and customer-sideand recommend a "time-dependent reliability" model, which tracks a customers storage over time. By plotting a variety of data on the systems and their failures (and a bunch of other points) and then applying a number of statistical voodoo, customers can get a better picture of reliability.Such events rarely seem to happen under warranty. In a similar vein, John Weinhoeft, of Springfield, Ill., suggested that warranties can be used as a predictor of disk reliability. Now retired, he was the former manager of a 21TB high-performance computing storage operation. "For enterprise operations, a better indicator was the maintenance rate charged for 24/7/365 service. The vendors knew what it was costing them to repair or replace failed units and adjusted their rates accordingly. When the projected maintenance cost over the next three years equaled new purchase cost plus a three-year warranty, it was time to replace the disk subsystem." According to Weinhoeft, this meant replacing most disk subsystems every three years. But when it comes to PC drives, he said that all bets are off as to reliability. "The treatment in the field is ridiculous. The average person doesnt have a clue how delicate the drives are. I regularly see people ruining systems," he said. He then related a story about dealing with a friend over an "Ethernet cable problem," or so it was described over the phone. It turned out that Weinhoefts friend had pushed the networking card completely out of the slot. "When I got there she still had the system powered on, was slamming the box left and right about 24 degrees each way trying to shake the card back in place and was fishing around in the live box with an oversize, unbent paper clip. And people wonder why their systems fail," he said. We can all smile at this and shake our heads knowingly. We would never, ever do anything as stupid as this in the enterprise or data center! However, as I mentioned in my previous column, many current IT storage techs appear to have taken on a somewhat cavalier attitude toward the handling of drives in the field. And I suggested that when folks toss around an iPod or a thumb drive or even some of the "ruggedized" external 2.5-inch notebook drives, they can pick up some bad habits when it comes to larger drives destined for desktops and servers. Some of you thought I was being overly cautious. Listen, I recall the same thing happening a generation ago with people in prepress shops handling Syquest cartridges and "real drives" housed in caddies for mirrored RAID systems. Both kinds of storage ended up being knocked around and given the same rough treatment. Same difference nowadays and still no good for the data. What do you think? Can your drives take a lickin? Or do you baby your disks? Let us know here. Check out eWEEK.coms for the latest news, reviews and analysis on enterprise and small business storage hardware and software.
One of the best methods to predict the failure of any device, storage or otherwise, is to simply count 30 days after its warranty. When the warranty is up, the product will fail. Or fall off your workbench onto the hard floor, warping the battery housing. Or a cup of coffee will be spilled on your desk and the liquid will drip down into the open vent and blow the power supply of the system stored below.