Problems Involving The Composite Links - Digital Equipment MUXserver 100 Reference Manual

This verifies the port operation. (Note: check that input and output
speed are the same.) This will identify a terminal port from a
Terminal Hardware Problem. For a terminal hardware problem, refer
to Section 4.4, PROBLEMS ADDRESSING INDIVIDUAL PORTS,
and carry out the troubleshooting procedures outlined.
If
it is a terminal port problem, check other terminal ports to deter-
mine if all 8 ports on the DECmux II unit are affected. If so,
go to
Section 4.3, PROBLEMS INVOLVING THE COMPOSITE LINKS,
for composite link problems.
If
the problem is limited to one or two terminal ports, suspect a
faulty DECmux II unit and return it for repair.
Go to Section 4.4 and carry out the troubleshooting procedures for
individual terminals.
If
you solve the problem for one of the termi-
nals, apply that solution to all the terminals.
4.3 PROBLEMS INVOLVING THE COMPOSITE LINKS
The status of the composite links are output to the supervisor port terminal of
the MUXserver 100 immediately after the completion of the image load and
hence diagnostic self tests. Any change in status of the links will also be out-
put to the supervisor port providing a session is not currently in progress.
NOTE
The link status message refers to Port A and Port B of the
MUXserver 100. If the multiplexer configuration given in Figure
4-1 is in use, the MUXserver 100 will show PORT B as being
DOWN (as it is not used) and it will not show the status of the
composite link between the two DECmux II units.
For a complete indication of the composite link status, use the MAP command
(see Chapter 5, Section 5.16, MAP). This command may be selected from the
'privileged mode' on the supervisor port of the MUXserver 100 by entering
COMM then MAP or from the supervisor port of either DECmux II unit by
entering MAP. Exit the MAP command by entering <CTRL/C>.
20 CHAPTER 4 MUXserver 100 TROUBLESHOOTING