Using Mobile Phone email addys for monitoring

Kevin Blackham blackham at
Fri Sep 7 03:48:42 UTC 2007

I would never trust SMTP for all the reasons already mentioned.  Primarily
if my network is dead, I still want to get paged about it.  Relying on the
import policy of another organization in the hostile port 25 environment is
also bad voodoo.

We've used a mix of TAP and SMS for many years with varying success.  When
the cell providers started dropping their TAP gateways, we went through a
few GSM modems.  First a Nokia on a cable, but the thing would do dumb stuff
like charge the battery, and with the cable connected go ahead and drain the
cells unless someone walked by daily and reseated the power cord.  Avoid
tethering phones, you will likely run into something to drive you nuts.
Next was a Sierra 750 PCMCIA GSM modem, which supported the standard AT
command set (I forget the ANSI spec).  That was fine once overcoming the
motherboard not assigning an IRQ, but once a week it'd stop responding to
commands and have to be reseated.

The final, ultimately reliable setup, which I recommend, was a Falcom Samba
75 USB GSM modem (quad band) talking to smstools.  With unlimited SMS plans,
two modems on separate networks, and some cron scripts, they could also
monitor each other every hour to ensure they were sending and receiving
pages.  We also did a daily "paging system is up on X" to oncall similar to
what another poster mentioned.  Also we configured smstools to call an error
script which'd send warnings another way (IRC in our case) if the modem
wasn't responding as expected (failed to send, receive or init).

On 9/6/07, Rick Kunkel <kunkel at> wrote:
> Hello folks,
> First off, apologies if this is off topic.  I'm hoping that system and
> network monitoring tip are enough of a common issue that this falls under
> the group's charter.
> We've traditionally used mobile phone email addresses for system
> notifications, but over the past 6-12 months, it seems to have become
> increasingly sketchy.
> For instance, if an application fails to contact a certain service on a
> certain server, it sends an email (through it's own SMTP service, to avoid
> a chicken-and-egg prob if/when our main SMTP service fails) to
> 1234567890 at  (Obviously, that was a fake number.)  More and
> more, I'm getting less and less of these notifications.
> It seems especially prevalent when MANY things are sent at once; if, for
> example, a central piece fails, and dependent pieces suddenly fail as
> well.
> I try to telnet to port 25 and get sometimes good,
> sometimes laggy, and sometimes no response.  T-Mobile, support levels all
> the way up to 3 tell me that it's not them, and everything should work
> wonderfully.
> Is SMTP to a mobile phone a fundamentally flawed way to do this?
> Anyone else have any issues, past or present, with this kind of thing?
> Thanks,
> Rick Kunkel
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