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Comment Break out the calculator and spreadsheet (Score 3, Informative) 260

Its time to break out the calculators and do some math. There are two main factors at work here, UPS load capacity and battery run time. I run a series of research clusters at a university, so only the core systems (landing pads, schedulers, auth, disk arrays) are on UPS and all the compute nodes just die at a power hit.

Retrofitting a datacenter for whole center UPS is a very daunting and expensive task, so odds are good you'll be replacing the current rack mounts with beefier units, either pedestal sized units next to their racks or rack mounted units.

When buying UPS gear for work, I aim to hit either 67% capacity with the planned load, or the smallest VA rating that takes 208V single phase, as long as its at least 1/3 under utilized for future expansion. That covers the VA rating. As for battery run time, most of the larger units accept external battery packs to increase the run time. I've never used them, since a 5KVA unit with my load gives me 20 minutes of run time, and if the power isn't back on by then, odds are good its not coming back any time soon.

Another option for extending UPS run time is to prioritize services/VMs. With the appropriate monitoring software on each host, you can configure each host to shutdown when the UPS estimates X minutes of battery time remaining or there have been Y minutes on battery, or both. Less load, more run time for the really important stuff. Almost every UPS I've used (APC, Tripp-lite, Powerware) comes with off the shelf software or there are opensource solutions (apcupsd, nut) for monitoring the UPS over serial, USB, or SNMP (Options vary with mfg and model). My shutdown schedule is: after 5 minutes on battery, power down the compute cluster landing pads. With 10 minutes remaining, power down the file servers with the archival data on them. With 6 minutes remaining, power down the primary file servers. With 2 minutes remaining, power down the auth box/network monitor/iLom control host (This is the only one that can't get powered on/monitored remotely).

Comment Check with the university (Score 5, Insightful) 272

Does your university have a backup solution you can make use of? The one I work at lets researchers onto their Tivoli system for the cost of the tapes. I think I've got somewhere in the neighborhood of 100TB on the system and ended up being the driving force behind a migration from LTO-2 to LTO-4 this summer. If you are going to go and role your own and use disks, I'd recommend something with ZFS - you can make a snapshot after every backup so you can do point in time restores.

Also, I'd recommend more capacity on backup than you have now to allow versioning. I was the admin for a university film production recently (currently off at I believe Technicolor being put to IMAX) and I've lost track of the number of times I had to dig yesterday's or last week's version off of tape because someone made a mistake that was uncorrectable.

Comment Re:Hardware RAID becoming less relevant every day. (Score 1) 171

I have data sets spanning multiple terabytes. One recent PhD graduate in the lab I support accumulated 20 TB of results during his time here. Even if I had highly reliable SSDs that never failed, I'd still toss the SSDs together in a zpool to get the capacities I need to accommodate a single data set. RAID is not just about redundancy. With SSDs, I'd probably use RAID5 instead of RAID6 just in case I had a freak bad drive, but RAID in some form is here to stay.
Silicon Graphics

Submission + - SGI Files for Chaper 11, plans to sell off assets

darkjedi521 writes: According to Bloomberg, SGI filed for Chapter 11 bankruptcy April 1st with plans to sell its assets to Rackable Systems unless another buyer is willing to come forward and pay a higher per share price than Rackable. According to the Mercury News, the sale is for $25 million, though the chapter 11 proceedings leave the possibility of sale to another entity open.

Comment Re:I saw LEDs used as colored stage lights (Score 1) 685

Last time I looked at LED stagelights about a year ago, the LED PAR64 can seemed to be a drop in replacement for 300W PAR56 lamps. Unfortunately, until intensity catches up to their higher wattage cousins, most of the stages I've worked on are going to keep dropping in 750W HPL, 1KW BVT, and 1K PAR64 lamps. The biggest advantage is its easier to get a blue of out an LED than a halogen, for obvious reasons, but losing the light among the other fixtures isn't really desired all the time.
Desktops (Apple)

Submission + - when Macs break

cyber-dragon.net writes: "I have long been a staunch supporter of Apple and Macs, bordering on but not quite a fan boy. My recent experience with trying to bring them into my department at work has been dissapointing. We had a Mac Pro (the big quad processor monster) die after four days. Ok, it happens, everything else has worked flawlessly. I even delt with the inevitable teasing about the siny new Mac being a lemon.
Well after almost four hours dealing with Apple Care, three hours dropping off and picking up my computer at different stores as per thier instructions trying to get this done quickly... I am beginning to wonder if Apple really wants business customers to rely on these machines. Much as I may dislike Dell like the rest of you... when my Linux box died it was fixed in four hours and I spent maybe 20 mintes of my time setting up the repair. I have spent seven hours of my time so far on this Mac and it still will not power up. Is this just me or have other people lost critical business machines to the depths of Apple Care inefficiency and lack of business level support?"
Businesses

Submission + - Whatever happened to superconductors?

AltGrendel writes: "Jonathan Fildes of the BBC wrote that 'In 1987, Ronald Reagan declared that the US was about to enter an incredible new era of technology. Levitating high-speed trains, super-efficient power generators and ultra-powerful supercomputers would become commonplace thanks to a new breed of materials known as high temperature superconductors (HTSC). "The breakthroughs in superconductivity bring us to the threshold of a new age," said the president. "It's our task to herald in that new age with a rush."

But 20 years on, the new world does not seem to have arrived. So what happened?'

He shares what he found in this article."
Space

Submission + - Lost Moon landing tapes discovered

de_smudger writes: For years 'lost' tapes recording data from the Apollo 11 Moon landing have been stored underneath the seats of Australian physics students. A recent search has uncovered them.

Recorded on telemetry tapes, they are said to be the best quality images of the landing (unconverted slow scan TV) yet to be seen by a public still fascinated by the early space race. These tapes were mislaid in the early 1980s on their way to NASA's Goddard Space Flight Centre in Greenbelt, Maryland.
KDE

Submission + - KDE on Windows

AlanS2002 writes: "This week's KDE Commit Digest tells about an installer for KDE on Windows and the problems the developers encountered setting up a working environment for KDE to run on. Many screenshots included, showing the first applications (such as Konqueror) running natively."
Software

Submission + - Forced hardware retirement

AlonzoTG writes: "I have been informed that I must upgrade my motherboard to a newer and more common type in order to maintain linux compatibility. In my enthuseasm to buy a SMP machine in 2003 I overlooked the fact that my Tyan Tiger MPX (S2466) wasnt very popular as a workstation and would develop serious compatibility issues only four years in to its fifteen year useful life span. Fedora Core cannot be installed on the machine, nor can my existing installation support OpenGL graphics without crashing. (an issue with the GART chip which the kernel still claims to support — it stopped working about eight months ago). If I were to accept this loss, which workstation class boards can I choose which will remain operable under Linux for the entirety of their useful lifespan? Is it possible to obtain a guarentee with respect to a specific board that it will continue to be supported?"

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