Re: [users@httpd] How to debug " AH00051: child pid 31929 exit signal Segmentation fault (11), possible coredump in /apps/httpd2.4"?

[Eric Covener]

On Linux, /proc/sys/kernel/core_pattern determines the filename and may
pipe it to a custom process (abrtd, systemd). If it's piped, you will need
to possibly configure it or extract the underlying core.

On Tue, Feb 11, 2025 at 7:11 AM o haya  wrote:

> Hi,
> This is a followup (but different problem) to a problem that I had posted
> about previously.
>
> In the earlier thread, I had been getting an "undefined symbol" problem,
> and actually, it turned out that I had encountered that problem, and solved
> it, years ago (almost 7 years ago, I think), but with an earlier Apache
> version.  I found the solution in an old document that I had written when I
> first encountered that "undefined symbol" problem.  I was able to resolve
> that by using a "LoadFile xxx.so".
>
> Anyway, the problem I am trying to figure out now is that I am getting a
> segmentation fault:
>
> " AH00051: child pid 31929 exit signal Segmentation fault (11), possible
> coredump in /apps/httpd2.4".
>
> The Apache starts up with no problem, but as soon as I try to do a test
> request to the Apache, I am getting that segmentation fault in the Apache
> "error_log".
>
> I've been trying to find out what is causing that segmentation fault, but
> I'm not quite sure how to find the coredump  that is mentioned (FYI, there
> is no coredump files in /apps/httpd2.4).
>
> Can someone explain how I can find the coredump and also how I can see
> what is in the coredump to try to figure out what is wrong?
>
> Thanks,
> Jim
>
>
> 
> Virus-free.www.avast.com
> 
> <#m_3410527433174136096_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>


-- 
Eric Covener
cove...@gmail.com

[users@httpd] How to debug " AH00051: child pid 31929 exit signal Segmentation fault (11), possible coredump in /apps/httpd2.4"?

[o haya]

Hi,
This is a followup (but different problem) to a problem that I had posted
about previously.

In the earlier thread, I had been getting an "undefined symbol" problem,
and actually, it turned out that I had encountered that problem, and solved
it, years ago (almost 7 years ago, I think), but with an earlier Apache
version.  I found the solution in an old document that I had written when I
first encountered that "undefined symbol" problem.  I was able to resolve
that by using a "LoadFile xxx.so".

Anyway, the problem I am trying to figure out now is that I am getting a
segmentation fault:

" AH00051: child pid 31929 exit signal Segmentation fault (11), possible
coredump in /apps/httpd2.4".

The Apache starts up with no problem, but as soon as I try to do a test
request to the Apache, I am getting that segmentation fault in the Apache
"error_log".

I've been trying to find out what is causing that segmentation fault, but
I'm not quite sure how to find the coredump  that is mentioned (FYI, there
is no coredump files in /apps/httpd2.4).

Can someone explain how I can find the coredump and also how I can see what
is in the coredump to try to figure out what is wrong?

Thanks,
Jim


Virus-free.www.avast.com

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

Re: [users@httpd] How to debug " AH00051: child pid 31929 exit signal Segmentation fault (11), possible coredump in /apps/httpd2.4"?

[o haya]

I have been encountering a problem trying to work with the core dump file.
After I decompress the lz4 file and then try to use gdb (gdb
/apps/httpd2.5/bin/httpd ), I am getting an error msg in GDG:

Reading symbols from /apps/httpd2.4/bin/httpd...done.
"/var/lib/systemd/coredump/core.httpd.1001.9e14cb0299404a82a8df5c73ceab0e83.53762.173930562400"
is not a core dump: file truncated

If I run 'file' on the core file I get:
[root@localhost coredump]# file /tmp/core.31929
/tmp/core.31929: ERROR: ELF 64-bit LSB core file, x86-64, version 1 (SYSV)
error reading (Invalid argument)

Does anyone know what might be causing this?

I even worked with one of my colleagues and we tried increasing limits,
etc., but to no avail.

Thanks!
Jim


Virus-free.www.avast.com

<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Tue, Feb 11, 2025 at 8:30 AM o haya  wrote:

> Ahh... so something like this?
>
>  gdb /apps/httpd2.4/bin/httpd -c /tmp/core.31929
> .
> .
> For help, type "help".
> Type "apropos word" to search for commands related to "word"...
> Reading symbols from /apps/httpd2.4/bin/httpd...done.
> "/tmp/core.31929" is not a core dump: file truncated
>
> Do you know why it is it saying it isn't a core dump?
>
>
>
> 
> Virus-free.www.avast.com
> 
> <#m_3423562340961458741_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>
> On Tue, Feb 11, 2025 at 8:18 AM Eric Covener  wrote:
>
>> No, you're expected to extract it and look at it with gdb.
>>
>> On Tue, Feb 11, 2025 at 8:17 AM o haya  wrote:
>> >
>> > Here's an example of the coredumpctl - is the the only info that the
>> coredump can provide?
>> > [root@localhost coredump]# coredumpctl dump 31929 --output
>> /tmp/core.31929
>> >PID: 31929 (httpd)
>> >UID: 1001 (orcladmin)
>> >GID: 1001 (orcladmin)
>> > Signal: 11 (SEGV)
>> >  Timestamp: Tue 2025-02-11 06:54:34 EST (1h 20min ago)
>> >   Command Line: /apps/httpd2.4/bin/httpd -k start
>> > Executable: /apps/httpd2.4/bin/httpd
>> >  Control Group: /
>> >  Slice: -.slice
>> >Boot ID: 9e14cb0299404a82a8df5c73ceab0e83
>> > Machine ID: f12d5da85f9443838815a7764fc748c0
>> >   Hostname: localhost.localdomain
>> >Storage:
>> /var/lib/systemd/coredump/core.httpd.1001.9e14cb0299404a82a8df5c73ceab0e83.31929.173927487400.lz4
>> (truncated)
>> >Message: Process 31929 (httpd) of user 1001 dumped core.
>> >
>> > Virus-free.www.avast.com
>> >
>> > On Tue, Feb 11, 2025 at 7:56 AM Eric Covener  wrote:
>> >>
>> >> coredumpctl list and confirm it has an entry for the affected PID
>> >>
>> >> Extract the core file to a location with enough space: coredumpctl
>> dump $PID --output /tmp/core.$PID
>>
>>
>>
>> --
>> Eric Covener
>> cove...@gmail.com
>>
>