topic Re: analyze core dump in Operating System - HP-UX

analyze core dump

Dagmar Boelen — Thu, 03 Jul 2003 11:27:28 GMT

I Found several core dumps on my system. My first question is how can I analyze these core dumps? On which location are these dumps usually created? Can the kernel itself create a core dump? and what about a application dump?

Re: analyze core dump

Steven E. Protter — Thu, 03 Jul 2003 11:33:00 GMT

Quick and dirty way is:

strings core | more

You can get some useful information from that.

If oracle or some other application creates a dump, the same command may or may not be effective. You have to see the vendor for that.

Kernel problems can create dumps, but if they are serious, the box wont boot in the first place, you'll get a kernel panic at boot time.

SEP

Re: analyze core dump

Massimo Bianchi — Thu, 03 Jul 2003 11:33:40 GMT

Hi,
everything can do a dump.
When is the kernel, your system does a "panic" and reboot.

To find the application that generates the dump,
usa the command "file" against the core.

Core can be anywhere.

To analyze a dump, there was a nice thread full of instruction...
i will search it.

HTH,
Massimo

Re: analyze core dump

melvyn burnard — Thu, 03 Jul 2003 11:40:25 GMT

There are different ways of getting a core dumped.
A program can core dump, leaving a file named core, in a directory usually where it was started from or in certain applications in specified directories. and example is where cmcld (serviceGuard daemon) core dumps and leaves a core file in /var/adm/cmcluster

You can look at these files using :
what
file
strings

A kernel or system panic will create a core dump, this normally goes into /var/adm/crash, and consists of mutiple file.
If you have had one of these, then you have had a serious problem at some time.
These normally need analysing by your local HP Response Centre
Hope that helps

Re: analyze core dump

Umapathy S — Thu, 03 Jul 2003 11:55:43 GMT

Dagmar,
All applications will core dump when encountering SIGSEGV and SIGBUS errors provided they have permission to dump.

You can analyze these core dumps through many commands.

file core will give which application and why
strings will print out all the info in the core which will be the superset of executable. So there will be too much information.
what gives also the necessary info.

kernel dumps and they can be analyzed to the good by q4.

applications dumps can be analyzed by gdb. It can pinpoin the error if the debug flag is set. You can print the stack trace to get to the exact place where it got dumped.

HTH,
Umapathy

Re: analyze core dump

twang — Thu, 03 Jul 2003 12:03:38 GMT

You may refer to this thread:
http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xc4db506d69a7d711abdc0090277a778c,00.html
Hope it help you a bit.
twang

Re: analyze core dump

Fragon — Thu, 03 Jul 2003 12:50:45 GMT

Hi,
A good tool in HP-UX for analyze core dump is q4. You can get the English version manual of q4 here:
http://hpux.0451.net/download/q4docs.zip

-ux

Re: analyze core dump

Steven E. Protter — Thu, 03 Jul 2003 20:10:43 GMT

You can't analyze core dumps with q4. It works with crash dumps in /var/adm/crash

Please post a procdure for using it on core dumps, I'd like to know how.

SEP

Re: analyze core dump

Caesar_3 — Thu, 03 Jul 2003 20:15:49 GMT

Hello!

For the begin you can use the what command
and for more you have the q4 script
to debug the core dump.
More info about the q4 is on the
docs.hp.com

Caesar