PCI Token Ring Administrator's Guide

Troubleshooting Token Ring

Diagnostic Flowcharts

Chapter 4 103

Flowchart 7 Procedures

A. Execute telnet to remote host. Try to establish a telnet connection

to the remote host.

B. Successful? If your telnet attempt was successful, stop. The

connection is ok through the Transport Layer (OSI Layer 4).

C. Execute ftp to remote host. Unlike telnet, ftp does not go through

a pseudo terminal driver (pty) on your system. This step tests to see

if the pty is why telnet failed.

D. Successful? If ftp is successful, you likely have a problem with a pty

on your system. Contact your HP representative.

E. TCP conﬁgured on local or remote host? Neither telnet or ftp

will work if TCP is not conﬁgured on either side of the connection.

Check the /etc/protocols ﬁle on both hosts to be sure TCP is installed

and conﬁgured.

F. Network congested? If so, the system administrator should

determine the cause of the congestion. First, determine if there is a

problem with any one of the nodes; there may be a hardware problem

causing the congestion. Bridges or switches may be added so that the

number of nodes in each loop is reduced. This should reduce the

congestion.

If not, call HP support for help in resolving the problem.

If TCP is installed on both hosts, do a ﬁle transfer to another remote

host on the network. Use netstat to check for lost packets.

G. Conﬁgure TCP. If necessary, conﬁgure TCP on either or both hosts.

Check for the presence of inetd and a properly conﬁgured

/etc/inetd.conf.