Path: utzoo!attcan!uunet!husc6!mailrus!ncar!ames!pasteur!ucbvax!dsunx1.dsrd.ornl.gov!wnn
From: wnn@dsunx1.dsrd.ornl.gov (W. N. Naegeli)
Newsgroups: comp.protocols.appletalk
Subject: Responder problems
Message-ID: <8811172050.AA05789@dsunx1>
Date: 17 Nov 88 20:50:07 GMT
Sender: usenet@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 22

We have recently had a great deal of problems and lost many hours to detective
work until we found Apple's Responder as the culprit.  Responder is an INIT
that comes with System software 6.0.2 and is intended to be used on every
networked Mac when the network administrator uses Apple's Inter*Poll software
to check on network integrity.
     The problem affected Mac Plus users of NCSA Telnet 2.2 and TCP/Connect.
In most cases, when the user tried to open a connection, she or he would get
a message that Telnet (or TCP/Connect) could not connect to the host and a
second message stating that the Local host or Gateway was not responding.
If a connection was established, it was usually extremely sluggish, with long
delays until characters entered at the keyboard would be echoed, and pauses
of up to 30 seconds during the display of long text documents.  Sometimes
the connection simply timed out in the middle of a session.  Interestingly,
this problem was not experienced by a Mac II user on the same LocalTalk
segment as the Mac Pluses.
      The "Local host or gateway not responding" message misled us.  After
checking the host, restarting and finally even replacing the KFPS-3 gatway,
we finally concentrated on the AppleTalk traffic on the LocalTalk segment
and found, that the affected Macs seemed not to process the majority of
AppleTalk packets addressed to them.  Finally, after removing other Apple
Talk INITs we removed Responder on one of the machines, and our TCP performance
was suddently back to normal.