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Catalyst 3750 Switch Hardware Installation Guide
OL-6336-07
Chapter 1 Product Overview
10/100 and 10/100/1000 Ports
To select or change a mode, press the Mode button until the desired mode is highlighted. When you
change port modes, the meanings of the port LED colors also change. Table 1-6 explains how to interpret
the port LED colors in different port modes.
Table 1-6 Meaning of LED Colors in Different Modes on the Switch
Port Mode Port LED Color Meaning
PoE
1
Off PoE is off. If the powered device is receiving power from an AC
power source, the port LED is off even if the powered device is
connected to the switch port.
Green PoE is on. The port LED is green only when the switch port is
providing power.
Alternating
green and
amber
PoE is denied because providing power to the powered device will
exceed the 370 W switch power capacity.
Blinking amber PoE is off due to a fault.
Caution PoE faults are caused when noncompliant cabling or
powered devices are connected to a PoE port. Only
standard-compliant cabling can be used to connect Cisco
pre-standard IP Phones and wireless access points or
IEEE 802.3af-compliant devices to PoE ports. A cable or
device that causes a PoE fault must be removed from the
network.
Amber PoE for the port has been disabled.
Note PoE is enabled by default.
STAT
(port status)
Off No link, or port was administratively shut down.
Green Link present.
Flashing green Activity. Port is sending or receiving data.
Alternating
green-amber
Link fault. Error frames can affect connectivity, and errors such as
excessive collisions, cyclic redundancy check (CRC) errors, and
alignment and jabber errors are monitored for a link-fault
indication.
Amber Port is blocked by Spanning Tree Protocol (STP) and is not
forwarding data.
Note After a port is reconfigured, the port LED can remain amber
for up to 30 seconds as STP checks the switch for possible
loops.
Flashing amber Port is blocked by STP and is sending and receiving packets.
DUPLX
(duplex)
Off Port is operating in half duplex.
Green Port is operating in full duplex.
