tcpdump -vvv -i eth0 -s 0 port bootps
debugging
All posts tagged debugging
Using shell debugging on execution
set -o verbose
set -o xtrace
I am by no means an expert in this, but here is how to determine what caused the core dump.
A core dump looks like the following.
core.38240
The number usually is the PID of the program that crashed, however most of the time this hasn’t been very helpful..at least for me.
First figure out what program caused the issue, normally I just use some binary that most likely didn’t cause the issue, like here I use /bin/ps. Usually the last section will say, the binary your specifying doesn’t match the core file which is whatever program. =) In this example, /usr/sbin/ndsd.
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sudo gdb /bin/ps core.38240 |
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. . . warning: core file may not match specified executable file. Core was generated by `/usr/sbin/ndsd'. Program terminated with signal 4, Illegal instruction. #0 0x58c3376a in ?? () |
Once we got the correct program, exit from this and run it again with the correct binary.
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sudo gdb /usr/sbin/ndsd core.38240 |
more to come…
