Friday, March 12, 2004

Two Army Problem

Two articles that I found interesting:

Two Army Problem / Byzantine Generals Problem

Impossibility of distributed consensus with one faulty process

posted by Wuphon's Reach at 5:49 PM

Tuesday, March 09, 2004

Socket A Cooling

Found my notes... the CPU fan in the beast is an old ThermalTake Super Mini Orb. Air flow for the lower fan is 25.5cfm and the upper fan pushes 17cfm. Rather noisy critter at 32-34dBA for both fans which spin at 5000-5500rpm.

So I need something quieter... Eventually, I'd like to replace the (6) 7200rpm IBM DeskStar 75Gb drives with quieter 160Gb or 200Gb drives. But I think I'm going to hold off on that until the fall at the earliest. The system is stable, and I dread the 40+ hours it would take to upgrade and format the new array. I'll still do it at some point because a 275Gb array is starting to feel small now that I'm working with video files that are usually 5-15Gb. The 160Gb drives would bump me up to 550Gb in the array, while 200Gb drives should bump me to 750Gb. Which is a heck of a lot of space, but HDTV, DV and video capture files are all in the 10-13Gb/hr range. Multiply by 3 if you're going to do any editing/encoding. I have 100Gb free on the server and 100Gb free on the capture workstation, and it's not unusual for me to have to stop for a while to move video files around because I'm out of room on one box or the other. (That's a different can of worms, that it takes an hour to move 12-16Gb across the network, but I'm upgrading to gigabit ethernet next week to fix that.)

FYI, the p160 case includes a pair of temperator monitoring thermistors that you can position anywhere whithin the case. I have one hovering up in front of the power-supply (directly behind the top 5.25" exterior bay) and the other is down in the middle, roughly centered over the motherboard. Now, I'm not sure which is which, but one reports a temperature of 40-41C and the other reports in at 34-35C, ambient temperature in the office is currently 24C (75F). Since the CPU is running at 100% due to the PrimeNet client, it probably will never get much worse (motherboard reports the CPU temp as 50-52C).

posted by Wuphon's Reach at 3:03 AM

Monday, March 08, 2004

Antec p160 Case

Changed my mind on upgrading my noisy server. I was going to go with the Antec Sonata case which is part of Antec's LifeStyle Series. The Sonata is a piano-black "quiet" case with large 120mm fans and a few other features that are supposed to quiet things down. However, it only has (3) exposed 5.25" bays on the front which would be limiting should I choose to later upgrade to a 3Ware 3-bay/4-drive SATA hot-swap system. So I need (4) exposed 5.25" bays on the front.

Enter the Antec p160 case, which is almost identical in size/features to the Antec Sonata, but is aluminum, comes with (4) exposed 5.25" bays, and includes some other fancy features such as front temperature display. Not sure if it will be as quiet as the Sonata would have been, but the interior layout is almost identical and anything would be better then the ~50-55dB monster that I currently have humming away. (The monster has (6) 7200rpm drives, each with it's own pair of 30-40mm cooling fans. Definitions of decibel levels) Hopefully, I can drop the case noise down to a respectable 40dB, or at least make it so that server box isn't the noisiest thing in the office.

Well, it took 3 hours to move everything from the old full-tower case (SuperMicro 750A) to the new Antec p160 case. First (and not counted in the 3 hours) I made sure that I had full backups of everything on the 6-drive RAID set. The second thing that I had to do was make sure that I completely and thoroughly identified and labeled which of the 6 drives in the array were connected to which port on the Promise SX6000 RAID card. Then I double-checked and triple-checked those markings to make sure that I had gotten it right (since I was moving an active system).

Moving the actual parts from the old to the new was pretty simple, the only scare that I had is that the Promise SX6000 is a full-length PCI card, and the Antec p160's (4) drive bays at the bottom will interfere with full-length cards. Eek! Fortunately, they've left a gap at the bottom, presumably for just such a situation - but that means there's only one possible slot to put the SX6000 card in. (I was hoping to keep all of the cards in the exact same slots prior to the move to avoid confusing Windows when I powered back up...) The other problem is that putting the SX6000 in the only possible slot results in it overlapping some pins on the motherboard (power LEDs, power switch, reset switch, etc.). I did manage to fit everything in, but the power switch wiring did get a little cramped.

The 120mm fan that came with the Antec p160 ended up as the front fan (broke the rubber mounting tails that came with it too). Bought a 2nd Antec fan (Pro 120mm DBB Fan) and installed that as the exhaust fan by the power-supply. Hooked both fans up to the TruePower power-supply's "FAN" 4-pin molex connectors so that the power-supply controls the RPMs. The old power-supply was only a 300W (eep) while the new one is a 480W, that may help with any possible issue that I was having with hard drives randomly powering down.

Now, for the noise results... it's better, but not there yet. I definitely need to replace the cylindrical style heat sink on the CPU (don't remember the make off-hand) because that's still putting out a good bit of noise. The rest of the system seems quiet enough that I'm hoping when I replace that I'll have my desired result.

The new case is also about 8-9" shorter then the old SuperMicro case, but an inch or two deeper. In my case, shorter is good because I can then stack the external USB drives on top of the case instead of beside it.

Pictures:

The old Super Micro SC-750 case and labeling of the (6) RAID cables prior to transferring the Promise SX6000 card and the (6) hard drives to the new Antec case.


Empty interior / Bottom hard drive bays (I do wish the Antec TruePower 480 supply came with a few more 4-pin power connectors as I had to use (3) Y-adapters in order to get everything plugged in.)


Front of the Antec p160 case


Here's how the full-length SX6000 card interacts with the bottom hole in the inside drive-rack. Although it looks like a tight fit, there's actually 0.5" of clearance all the way around (or more). Also a close-up of the problem where the full-length SX6000 card interferes with the Abit KT7-RAID status/control pins.


Noisy CPU fan that needs to be replaced


posted by Wuphon's Reach at 10:09 AM