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In /var/log/messages, this error occurred:

Sep 19 13:18:15 wdc kernel: [2772302.630416] Machine check events logged

Shortly there after, the entire server became unresponsive. This is in the log of the Dom0 for a Xen Server (running the latest version on Debian Squeeze).

Can anyone shed some light on what this error means? Should I be ordering new hardware?

Edit: Also, it seems to imply it logged something, where can I find that?

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up vote 5 down vote accepted

For more information check logfile (this log file might be there or might not be, it depends how it is configured in /etc/mcelog/mcelog.conf) where should be detail description of the problem found.


or just run command


Mcelog is decoding kernel machine check log on x86 machines. From man mcelog:

X86  CPUs  report  errors  detected by the CPU as machine check events (MCEs).  These
can be data corruption detected in the CPU caches, in main memory by an integrated
memory controller, data transfer errors on the front side bus or CPU interconnect or
other internal errors. Possible causes can be cosmic radiation, instable power
supplies, cooling problems, broken hardware, or bad luck.
Most  errors  can  be  corrected by the CPU by internal error correction mechanisms.
Uncorrected errors cause machine check exceptions which may panic the machine.
When a corrected error happens the x86 kernel writes a record describing the MCE into
a internal ring buffer available through  the  /dev/mcelog device  mcelog retrieves
errors from /dev/mcelog, decodes them into a human readable format and prints them on
the standard output or optionally into the system log.

You can find more information about mcelog and its configuration/errors/triggers on the project webpage Mcelog project webpage

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