Telnet connection closes immediately upon connecting

[Kristoffer Knigga]

Hello all,

I have a legacy application that I have running on a couple of RHEL AS
4.5 servers that requires telnet connections.  We are currently in the
process of fixing this requirement, but I digress.  This weekend we
rolled out a new server with this application and soon after users
started hitting it this morning telnetd started dropping new connections
as soon as they were made.  By all accounts, existing telnet sessions
and ssh were unaffected.

Example:
$ telnet localhost
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
Connection closed by foreign host.

This can be fixed by simply restarting xinetd, but it's kind of
annoying.  I haven't been able to find a pattern yet as to what triggers
this, either.  I've checked iptables and tcp wrappers, but neither
looked to be the culprit.  /var/log/messages looks clean, too.

Any thoughts on either how to resolve this or get more information?

Kris


____________________________________________
Kristoffer Knigga
Systems Administrator
Arrow Financial Services
kknigga at arrow-financial.com
847-324-7962