3Com 5101T-FB-ST, 5101T-FB-SMA, 5101T-FB-FC manual Troubleshooting Link Problems

Table 6. Troubleshooting Using the Status LEDs

LED	Indicates	Possible	Possible
Status		Problem	Solution
5	Invalid	Broken or	Check and fix
Blinks	data	degraded	RX fiber link
(con’t)		fiber
		Bad or	Try another
		degraded	port or
		port on other	replace unit
		end

Troubleshooting Link Problems

Each full duplex fiber link is monitored at both ends. The 10BASE-FB Star Coupler and the 3Com Ethernet 10BASE-FB Modules contain status indicators (one for each port). The Transceiver contains a single status indicator. In addition to signifying link problems, the Transceiver indicator also indicates a local or remote jabber condition.

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