Re: [cobalt-users] MX Records and failover servers

["E.B. Dreger" <eddy+public+spam@xxxxxxxxxxxxxxxxx>]

JL> Date: Thu, 23 May 2002 14:32:59 -0700
JL> From: Jeff Lasman

[ snipped ]


JL> I've always understood that ETRN was to a fixed IP# set up in
JL> the server holding the mail, so I don't see why random people
JL> "tickling" the queue would do more than create a minor
JL> annoyance.  Am I missing something?  Is my understanding of
JL> how ETRN works a bit incomplete?

The destination IP is fixed, true.  By default, however, anyone
can connect to an ETRN-enabled Sendmail box and request ETRN on
any domain serviced by that machine (any domain at all?).

No big deal when the queue is small.  With a large queue,
however, it's conceivable that one could DoS an MX via repeated
ETRN commands.


--
Eddy

Brotsman & Dreger, Inc. - EverQuick Internet Division
Phone: +1 (316) 794-8922 Wichita/(Inter)national
Phone: +1 (785) 865-5885 Lawrence

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