3Com 5104M-FL1 installation and operation guide RFS Troubleshooting, Technical Assistance

Table 4-2. Troubleshooting Using the Port Status LEDs

LED State	Indication	Possible Cause	Corrective Action
3 Blinks	FIFO error or	Bad unit or	Try another port or
(continued)	MAU	non-10BASE-FL	replace other unit.
	jabber	equipment at
	lockup	other end.
	protection
		Bad 10BASE-FL	Replace module.
		Module.

RFS Troubleshooting

When you enable redundancy for a port on one 10BASE-FL Module (splices), you must enable Remote Failure Signaling (RFS) on the corresponding port of the remote 10BASE-FL Module to which it is connected. If you accidentally enable RFS on both sides of a 10BASE-FL link, the link may fail because each side “thinks” it is the remote end of the link.

In addition, when you enable redundancy on both sides of a 10BASE-FL link and the primary port fails, the backup port on the remote end of the link does not take over because the port “thinks” it is the primary port.

Technical Assistance

You can receive assistance for installing and troubleshooting the 10BASE-FL Module by calling either your 3Com reseller or 3Com Technical Support. Be prepared to supply a representative with the following information:

❑Description of the problem

❑Steps you have taken to try and correct the problem

❑Type and software version of the ONline management module being used

Troubleshooting 4 - 5