computer puzzler (with solution)
Jan. 8th, 2004 10:13 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
eorFor those who think you're computer savy, here is a wierd troubleshooting scenario for you: An underutilized FreeBSD box that hasn't had significant software or hardware changes in months, on a private network. The box began to infrequently (at least at first) lock up. It would sound like it was running and if you looked at the screen it still showed the console text, but the machine would not respond to keyboard or network input. Power cycle and things would come back up fine with no logs or garbled data. The problem increased in frequency. It became apparent that a) even idle the machine would eventual fail and b) under load (heavy disk IO) the system would fail quicker.
Now stop and think about the problem and come up with your top few avenues of attack.
If you chose:
Video card: I'm with you. Easy to change, always one around somewhere, tend to cause lockups when failing. Unfortunately, changing the video card only meant I got to dust off my spare.
Memory: Yeah, I can see that. Easy to change, so it's worth a shot. Anyway, these sticks were probably ones that got pulled out of a router years ago during an upgrade. That was a good exercise, but it's still locking up.
CPU: Yes, by some luck and coincidence I can actually test the CPU from that machine in another. Well, that CPU is actually faster than the one that was in my windows PC and since it works so well, I'll just keep it there. The FreeBSD box is still failing.
Motherboard: By chance, I just happen to have a motherboard I could swap out. Funny, the frozen screen looks just the same with this motherboard powering it.
Miscellaneous PCI cards: Just in case I pulled out the sound and network card. You really didn't think that would help did you?
CD Rom: Are you kidding? I unplugged that to get it out of my way when I was changing the memory. No, that's not it.
Hard Drive: I can't bear the thought of it. Yeah, you may be right, but I've already changed out the small/boot drive and the big drive has my entire CD collection ripped to MP3's on it. I can just take it out, set it aside, and see what happens. Fortunately, those of you who guessed the drive were wrong! The machine failed even while I was shopping for a replacement and the drive was sitting on my desk
What component does that leave?
Power Supply: If you guessed this, you have way too much experience with dead power supplies. I've seen them die in smoke. I've seen them die in silence. But this is the first time I've seen one that could die while still powering video, fans, etc.
Now stop and think about the problem and come up with your top few avenues of attack.
If you chose:
Video card: I'm with you. Easy to change, always one around somewhere, tend to cause lockups when failing. Unfortunately, changing the video card only meant I got to dust off my spare.
Memory: Yeah, I can see that. Easy to change, so it's worth a shot. Anyway, these sticks were probably ones that got pulled out of a router years ago during an upgrade. That was a good exercise, but it's still locking up.
CPU: Yes, by some luck and coincidence I can actually test the CPU from that machine in another. Well, that CPU is actually faster than the one that was in my windows PC and since it works so well, I'll just keep it there. The FreeBSD box is still failing.
Motherboard: By chance, I just happen to have a motherboard I could swap out. Funny, the frozen screen looks just the same with this motherboard powering it.
Miscellaneous PCI cards: Just in case I pulled out the sound and network card. You really didn't think that would help did you?
CD Rom: Are you kidding? I unplugged that to get it out of my way when I was changing the memory. No, that's not it.
Hard Drive: I can't bear the thought of it. Yeah, you may be right, but I've already changed out the small/boot drive and the big drive has my entire CD collection ripped to MP3's on it. I can just take it out, set it aside, and see what happens. Fortunately, those of you who guessed the drive were wrong! The machine failed even while I was shopping for a replacement and the drive was sitting on my desk
What component does that leave?
Power Supply: If you guessed this, you have way too much experience with dead power supplies. I've seen them die in smoke. I've seen them die in silence. But this is the first time I've seen one that could die while still powering video, fans, etc.
