3Com DUA 1648-5AAA02 manual SFP Ports, Link/Activity Status LEDs, Status Meaning

CAUTION: The Switch supports full duplex auto-negotiation. If auto-negotiation is disabled for 1000BASE-T, then the Switch uses the forced-mode default of 100 full duplex mode. If the connected device does not support auto-negotiation, the Switch will operate in half duplex mode (even if the attached device is operating in full duplex mode). In such a configuration, you may notice some degradation of network performance. 3Com recommends that you use devices that are capable of auto-negotiation (and that you ensure that auto-negotiation is enabled, if it is a configurable option).

2 SFP Ports

The Small Form Factor Pluggable (SFP) ports are numbered 13 to

16.If an SFP transceiver (purchased separately) is installed in a slot and is active, the associated RJ-45 port of the same number is disabled.

The four SFP ports support fiber Gigabit Ethernet short-wave (SX) and long-wave (LX) SFP transceivers in any combination. This offers you the flexibility of using SFP transceivers to provide connectivity between the Switch and remote 1000 Mbps workgroups or to create a high-capacity aggregated link backbone connection.

SFP ports are numbered 13-16 on the Switch. When an SFP port is active it has priority over the 10/100/1000 port of the same number. The corresponding 10/100/1000 port is disabled when an SFP transceiver is plugged in.

3 Link/Activity Status LEDs

The following table lists LEDs visible on the front of the Switch, and how to read their status according to color.

Status	Meaning
Green	The link is operating at 1000 Mbps.
Yellow	The link is operating at 10 or 100 Mbps.
Flashing	Packets are being received or transmitted on the port at 1000
Green	Mbps.
Flashing	Packets are being received or transmitted on the port at 10 or
Yellow	100 Mbps.
Flashing	Port disabled or link loopback error.
Yellow to
Green
Off	The link has not been established, either nothing is connected
	to the port, or there is a problem:

■Check that the attached device is powered on.

■Check that the cable or fiber is the correct type and is not faulty.

■For fiber connections, ensure that the receive (RX) and transmit (TX) cable connectors are not swapped.

If these checks do not identify the cause of the problem, it may be that the unit or the device connected to the port is faulty. Contact your supplier for further advice.

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