Cisco Systems 3560 사용자 설명서

is a monitoring port, you might configure autostate exclude on that port so that the VLAN goes down 
when all other ports go down. When enabled on a port, autostate exclude applies to all VLANs that are 
enabled on that port.

The VLAN interface is brought up when one Layer 2 port in the VLAN has had time to converge 
(transition from STP listening-learning state to forwarding state). This prevents features such as routing 
protocols from using the VLAN interface as if it were fully operational and minimizes other problems, 
such as routing black holes. For information about configuring autostate exclude, see the 

EtherChannel port groups treat multiple switch ports as one switch port. These port groups act as a single 
logical port for high-bandwidth connections between switches or between switches and servers. An 
EtherChannel balances the traffic load across the links in the channel. If a link within the EtherChannel 
fails, traffic previously carried over the failed link changes to the remaining links. You can group 
multiple trunk ports into one logical trunk port, group multiple access ports into one logical access port, 
group multiple tunnel ports into one logical tunnel port, or group multiple routed ports into one logical 
routed port.Most protocols operate over either single ports or aggregated switch ports and do not 
recognize the physical ports within the port group. Exceptions are the DTP, the Cisco Discovery 
Protocol (CDP), and the Port Aggregation Protocol (PAgP), which operate only on physical ports. 

When you configure an EtherChannel, you create a port-channel logical interface and assign an interface 
to the EtherChannel. For Layer 3 interfaces, you manually create the logical interface by using the 
interface port-channel global configuration command. Then you manually assign an interface to the 
EtherChannel by using the channel-group interface configuration command. For Layer 2 interfaces, use 
the channel-group interface configuration command to dynamically create the port-channel logical 
interface. This command binds the physical and logical ports together. For more information, see 

Some Catalyst 3560 switches support dual-purpose uplink ports. Each uplink port is considered as a 
single interface with dual front ends—an RJ-45 connector and a small form-factor pluggable (SFP) 
module connector. The dual front ends are not redundant interfaces, and the switch activates only one 
connector of the pair. 

By default, the switch dynamically selects the interface type that first links up. However, you can use the 
media-type interface configuration command to manually select the RJ-45 connector or the SFP module 
connector. For information about configuring speed and duplex settings for a dual-purpose uplink, see 
the 

.

Each uplink port has two LEDs: one shows the status of the RJ-45 port, and one shows the status of the 
SFP module port. The port LED is on for whichever connector is active. For more information about the 
LEDs, see the hardware installation guide.