Nortel Networks 2500 Series manual Port connection problems, Autonegotiation modes

		Diagnosing and correcting problems 339
Table 153
Corrective actions
Symptom	Probable cause	Corrective action
All LEDs are off.	The switch is not	Verify that the AC power cord is fastened
	receiving AC power.	securely at both ends and that power is available
		at the AC power outlet.
	The fans are not	Verify that there is sufficient space for
	operating or the airflow
		adequate airflow on both sides of the switch.
	is blocked, causing the
	unit to overheat.	ATTENTION
		Operating temperature for the switch must
		not exceed 40￿C (104￿F). Do not place the
		switch in areas where it can be exposed to
		direct sunlight or near warm air exhausts or
		heaters.
The Activity LED for a	The switch is	See "Port connection problems" (page 339).
connected port is off or	experiencing a port
does not blink (and you	connection problem.
have reason to believe	The switch’s link
that traffic is present).
	partner is not
	autonegotiating
	properly.

Port connection problems

You can usually trace port connection problems to either a poor cable connection or an improper connection of the port cables at either end of the link. To remedy these types of problems, make sure that the cable connections are secure and that the cables connect to the correct ports at both ends of the link.

Port connection problems are also traceable to the autonegotiation mode or the port interface.

Autonegotiation modes

Port connection problems can occur when a port (or station) is connected to another port (or station) that is not operating in a compatible mode (for example, connecting a full-duplex port on one station to a half-duplex port on another station).

Nortel Ethernet Routing Switch 2500 Series

Overview — System Configuration

NN47215-500 (323162-B) 02.02 Standard

4.1 19 November 2007

Copyright © 2007, Nortel Networks