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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 13 Configuring Interface Characteristics
Using the Ethernet Management Port
Figure 13-3 Connecting a Switch Stack to a PC
By default, the Ethernet management port is enabled. The switch cannot route packets from the Ethernet
management port to a network port, and the reverse.
Even though the Ethernet management port does not support routing, you might need to enable routing
protocols on the port (see Figure 13-4). For example, in Figure 13-4, you must enable routing protocols
on the Ethernet management port when the PC is multiple hops away from the switch and the packets
must pass through multiple Layer 3 devices to reach the PC.
Figure 13-4 Network Example with Routing Protocols Enabled
In Figure 13-4, if the Ethernet management port and the network ports are associated with the same
routing process, the routes are propagated as follows:
• The routes from the Ethernet management port are propagated through the network ports to the
network.
• The routes from the network ports are propagated through the Ethernet management port to the
network.
Because routing is not supported between the Ethernet management port and the network ports, traffic
between these ports cannot be sent or received. If this happens, data packet loops occur between the
ports, which disrupt the switch and network operation. To prevent the loops, configure route filters to
avoid routes between the Ethernet management port and the network ports.
Ethernet management ports
Switch stack
Stack member 1
Stack member 2
Stack member 3
Stack member 4
Stack member 5
Stack member 6
Stack member 7
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PC
Hub
Catalyst 3750 switches do not have Ethernet management ports.
Catalyst 3750 switches in a mixed stack are not connected to the hub.
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Switch PC
Network
cloud
Network
cloud
Ethernet
management
port
Network
ports