Re: Conversations with an Ethernet watcher

Mike Karels (
Thu, 13 Feb 86 18:50:54 -0800

Dave, I was most tempted to flames by your first message in this series,
but restrained myself to see what other reactions would be. Fortunately,
others have beaten me to the punch.

Concerning the Unix mailer (sendmail), though, I'd like to add an
informational point. The major reason that multiple connections
are made to a single destination host is that mail is not queued
separately for each host. I have long wanted it to do so,
and I believe that the program's author now agrees. My reasons
have more to do with serializing the work when a major mail node
has been down or unreachable than with easing the task of the gateways.
If ucbvax is down for a day, innumerable connections are received
from everywhere as soon as it comes up. Only by cutting off
new connections when the machine overloads can it avoid disaster.
However, the amount of work required to change sendmail's way
of doing business is nontrivial, and I don't know who will take
on such a problem.


This archive was generated by hypermail 2.0b3 on Thu Mar 09 2000 - 14:35:40 GMT