Troubleshooting smtp(?)

[VirginSnow at vfemail.net]

> Date: Tue, 14 Apr 2009 20:43:57 -0400
> From: Curtis Sandoval <curtis.sandoval at gmail.com>
> Cc: gnhlug-discuss at gnhlug.org

> I've run into an odd problem.  I've been running python (2.5) scripts on a
> Linux box (Suse 10.2) for probably two years through cron.  These scripts
> email me using python's smtplib and the sample code from the Python
> documentation, and nothing has been changed on the o/s or the python or the
> Linksys wireless router that is hooked into my Roadrunner cable modem. (The
> machine itself runs with no monitor, I only shell into it and manage the
> scripts) On Monday I didn't get all of my expected messages, and I have
> ruled out nearly everything.  Roadrunner says it's my problem, but I
> suspected it was some sort of Conficker countermeasure.

If nothing changed on your side (no new packages, updates, out of disk
space, etc.), then it's probably due to a change in the SMTP or DNS of
your ISP.  Certain cable ISPs (to remain nameless) are notorious for
making configuration changes with no concern for their subscribers...
or, rather, under the assumption that their subscribers won't care...
or that they'll even notice.

If the DNS for your hostname (provided by your ISP's name server) has
been broken, for exmaple, your MTA (depending on its settings) may
fail to deliver messages and/or retry sending them for several days
before the message finally ends up bouncing... if the message bounces
at all.  Ant that's just ONE example of how your ISP can break your
mail overnight...

> My problem is that I didn't do anything explicit to set up the smtp
> functionality of my o/s

Well, there's you're problem!  If you don't know how your mail has
been routed, you have no way to know whether you mail has been working
only by coincidence, or by design.  I include in my definition of
"coincidence" any dependence upon unseen settings or configuration
under somebody else's control.