Cabletron Systems 520 - Manual (Page 79)

A-9
Problem Solving
Serial Port 1 or
Serial Port 2
Activity LED is
off. There is low serial port
activity or no serial port
activity. Ensure that serial port activity
is present. If the Serial Port
Activity LED still fails to turn
on, then turn the unit off by
removing it from the power
supply. Check that the Serial
Port Activity LED blinks
during the LED powerup self-
test.
If the Serial Port Activity LED
blinks, then the Serial Port
Activity LED portion of testing
has passed. If the Serial Port
Activity LED still fails to turn
on, then the router is defective.
Ensure that the cable
has activity on it. If the
LED still fails to turn
on, then the port is
defective. Replace the router.
Console
terminal does
not appear work. Wrong cable. Try connecting the console
terminal to the router using a
null modem cable with the
appropriate 8-pin MJ RS232
connector on the router end.
Wrong baud rate. Send a BREAK to the console
and then press <Return>
several times until the console
responds. Proper baud rates are
300, 1200, 2400, 4800, 9600,
19200, and 38400.
Defective router. Replace the router.
Table A-3. LED States
Symptom Probable Cause Corrective Action