How to trace a process?

classic Classic list List threaded Threaded
8 messages Options
Reply | Threaded
Open this post in threaded view
|

How to trace a process?

soko.tica
Hello list,

How to trace a process for debugging (4.6-stable, if that matters)?
I'm stuck with postfix+dovecot and need to discover why mail server
doesn't accept mail from my desktop.

RTFM's are fine, just point which one I should read. ;)

Thanks in advance.

Reply | Threaded
Open this post in threaded view
|

Re: How to trace a process?

Nick Guenther
On Tue, Dec 8, 2009 at 3:53 PM, soko.tica <[hidden email]> wrote:

> Hello list,
>
> How to trace a process for debugging (4.6-stable, if that matters)?
> I'm stuck with postfix+dovecot and need to discover why mail server
> doesn't accept mail from my desktop.
>
> RTFM's are fine, just point which one I should read. ;)
>
> Thanks in advance.
>
>

Trace? You mean like in a debugger? gdb comes with the system. You'll
probably have more luck reading dovecto and postfix's manpages to find
out how to crank their logging verbosity.

Reply | Threaded
Open this post in threaded view
|

Re: How to trace a process?

Ted Unangst-2
In reply to this post by soko.tica
On Tue, Dec 8, 2009 at 3:53 PM, soko.tica <[hidden email]> wrote:
> How to trace a process for debugging (4.6-stable, if that matters)?
> I'm stuck with postfix+dovecot and need to discover why mail server
> doesn't accept mail from my desktop.

ktrace is the program for tracing.  gdb is the program for debugging.
more is the program for looking at log files to discover the problem.
:)

Reply | Threaded
Open this post in threaded view
|

Re: How to trace a process?

Lars Nooden-2
Ted Unangst wrote:

> ktrace is the program for tracing...

Is there a common way for visualizing ktrace output, such as a script to
convert it to dotty or something similar?

Regards,
/Lars

Reply | Threaded
Open this post in threaded view
|

Re: How to trace a process?

Ted Unangst-2
On Tue, Dec 8, 2009 at 4:43 PM, Lars Nooden <[hidden email]> wrote:
> Ted Unangst wrote:
>
>> ktrace is the program for tracing...
>
> Is there a common way for visualizing ktrace output, such as a script to
> convert it to dotty or something similar?

kdump.  But I have no idea how you'd interpret the output as dotty.

Reply | Threaded
Open this post in threaded view
|

Re: How to trace a process?

Samiuela LV Taufa-4
In reply to this post by soko.tica
soko.tica wrote:

> Hello list,
>
> How to trace a process for debugging (4.6-stable, if that matters)?
> I'm stuck with postfix+dovecot and need to discover why mail server
> doesn't accept mail from my desktop.
>
> RTFM's are fine, just point which one I should read. ;)
>
> Thanks in advance.
>
>

trace may be the solution for you, but not having other information
about your problem, is it possible you can 'trace' your problem using
other tools / observations ? If the servers are running, you may need to
diagnose a little differently.

   * Is pf blocking traffic from the desktop ?

     - If telnet localhost 25 (and telnet localhost 110) works, but not
from desktop ?

   * What happens when you use telnet to connect with postfix smtp, or
dovecot imap/pop3 ?

I'm sure google can find you information for using telnet to test smtp,
pop3.

    e.g. http://www.nomoa.com/bsd/postfix.htm#4.1telnet
        http://www.nomoa.com/bsd/dovecot.htm

   * Are you monitoring /var/log/maillog ?
     - it generally has useful information on what Postfix / Dovecot
think is happening.
     - You can always bump up the noise level to dig in further ?


Sam T.

Reply | Threaded
Open this post in threaded view
|

Re: How to trace a process?

soko.tica
In reply to this post by Ted Unangst-2
On 12/8/09, Ted Unangst <[hidden email]> wrote:
> more is the program for looking at log files to discover the problem.
> :)

Well, not that I didn't deserve it with my phrasing. :)

Reply | Threaded
Open this post in threaded view
|

Re: How to trace a process?

soko.tica
In reply to this post by Samiuela LV Taufa-4
On 12/9/09, Samiuela LV Taufa <[hidden email]> wrote:
>     e.g. http://www.nomoa.com/bsd/postfix.htm#4.1telnet
>         http://www.nomoa.com/bsd/dovecot.htm

Many, many thanks, that was just what I need.