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My server recently just froze. I was unable to ping it, It did not respond to any keystrokes at all and the caps lock and scroll lock was flashing in unison with a steady off-on-off-on rate approx. once a second or so. Edit: My monitor was blank as well (that may be the monitor itself just for the record).

I am running Debian Squeeze with kernel 2.6.32-5-amd64 and the only software that I immediately suspect to be the cause of the panic could be VirtualBox 3.2.10 who I am using that runs a few VM's.

Anyway, I have been trying to find some information on the flashing keyboard led's to figure out if they can tell me anything about the reason for the panic but there is a lot of information from the kernel sending morse code to the kernel just indicating a crash.

What does the flashing leds mean (if anything) and how can I get more information about what caused the crash (if anything had time to end up on a physical disk that is).

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Is this a "headless" server? If it is, maybe you should attach a monitor for debugging, and post a picture of the panic. – BenjiWiebe Jan 10 '13 at 17:51
This is indeed a headless server, however I keep a monitor nearby so I can connect for situations like this. For this example the monitor was without signal. E.g. not only a black screen but in fact not even a signal. – Waxhead Jan 10 '13 at 18:27
Is BIOS okay? This may be a BIOS problem, even before you get to the kernel. – BenjiWiebe Jan 10 '13 at 18:36
My server froze hence it is not frozen :) e.g. everything is up and running fine. I am asking the questions to learn if the flashing leds' on a kernel panic means anything at all. – Waxhead Jan 10 '13 at 19:31
Oh... You should have said it thawed... ;) – BenjiWiebe Jan 10 '13 at 19:45

This has happened to me, due to a glitch (since fixed) with nVidia. Full freeze in Linux is rare, and without much, much further data next to impossible to diagnose.

One "popular" way to freeze a machine is that the CPU overheats and shuts down. Check the fans, shovel the dirt out, make sure nothing obstructs airflow, ...

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This is on a stock Debian Squeeze (and thus stable) without any additional stuff loaded up. I can guarantee you there is no overheat (rather the opposite in fact) so that is not the issue. Regardless the question was about understanding the meaning of the blinking lights (if any) so this is technically off topic. Thanks for your effort tough :) – Waxhead Jan 14 '13 at 20:57

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