[unisog] When you really need to blast email

James M. Blackburn BlackburnJ at brcc.edu
Tue Mar 11 18:37:19 GMT 2008

unisog-bounces at lists.dshield.org wrote:
> Our safety folks are working a campus-wide "emergency notice"
> system, where one option will be email (the logic behind that
> is outside the scope of this technical question).

I would argue that logic of selecting e-mail as a technology for
dispatching emergency notices is indeed within the scope of the
technical question.  Selecting an appropriate technology for a given
problem is always important, and I'm fairly certain that Internet e-mail
is not a great selection for dispatching emergency notifications.  The
reasons for this include the one you allude to below: we usually cannot
guarantee the proper transmission and delivery of a message over a
network that we do not control.

> Yahoo (and others) like to rate-limit email, and we've tried
> to no avail to remedy this .. usually we get a "421 try again
> later" (Yahoo). For things like our campus mail digest or
> notices of a snow day, a 15 minute delay isn't a problem. For
> something more serious like "stay inside and away from the window",
> it is. 
> My first thought was was to configure a box with multiple
> virtual IPs (possibly on different subnets) and blast them
> out in parallel with hopes of staying underneath the "radar"
> .. by doing multipath routing with Neftilter, for example
> (since I apparently can't do this with sendmail directly).
> Is there a better approach than this brute-force hack?

That may cause an angry system administrator to consider blocking your
entire allocation of IP addresses.  I would advise against it.  Would
you happen to have tried contacting anyone at Yahoo or any other free
e-mail provider about this?  If you must use Internet e-mail for
emergency notifications, working directly with the major e-mail
providers may help a lot.  They might be willing to make exceptions to
their rate-limiting if you explain the situation, especially in light of
the potential public relations impact.
Jim Blackburn
Blue Ridge Community College
blackburnj at brcc.edu

More information about the unisog mailing list