UDP port 69 connections.

[Barry Margolin <barmar@THINK.COM>]

    Date: Mon, 6 Nov 1989 13:11:59 PST
    From: price%iris.usc.edu@usc.edu (Keith Price)

    Has anyone else running on a network with a load of Suns encountered a
    problem of being swamped with UDP requests on prot 69 (A Sun trying to boot,
    but its boot server is down, it keeps trying, and trying, ...).  These have
    the nasty feature of absorbing all available memory.
	    This seems to affect systems with ECO tape#2 more than ECO tape#1
    (not all our systems are updated) and has become apparent only in the
    recovery from a power failure (every Sun is booting and some servers are
    still down) a few days ago.
	    Keith Price.

UDP port 69 is TFTP (Trivial File Transfer Protocol).  Diskless Suns use
this protocol to read their boot image.  They do it by sending a
broadcast, so the server will fire up on every Lispm on the net.

My solution was to disable the TFTP service on our Lispms.  Probably the
simplest way (although not the way I did it, because I just thought of
this a few minutes ago) is to do:

(setq tcp::*udp-protocol-alist*
      (delete 69 tcp::*udp-protocol-alist* :key #'car))

                                                barmar