Configuring A Dual-Purpose Port - Cisco ME 3400 Software Configuration Manual

Configuring Ethernet Interfaces

Configuring a Dual-Purpose Port

Some ports on the ME 3400-12CS and the ME 3400-2CS switches are dual-purpose ports that can be
configured as 10/100/100 ports or as small form-factor pluggable (SFP) module ports. Each
dual-purpose port is considered as a single interface with dual front ends (an RJ-45 connector and an
SFP module connector).
The dual-purpose ports are Gigabit Ethernet ports (gigabitethernet 0/1 through gigabitethernet 0/12 on
Note
the ME 3400-12CS and 0/1 and 0/2 on the ME 3400-2CS switch. Each switch also has standard SFP-only
module ports (gigabitethernet 0/13 through 0/16 on the Cisco ME 3400-12CS and 0/3 through 0/4 on the
ME 3400-2CS switch). Even when operating at 10 or 100 Mbps, the dual-purpose ports (and the
SFP-only module ports) use the frame size that is set with the system mtu jumbo global configuration
command.
Each dual-purpose port is considered as a single interface with dual front ends (an RJ-45 connector and
an SFP module connector). The dual front ends are not redundant interfaces; the switch activates only
one connector of the pair.
By default, the dual-purpose ports are user-network interfaces (UNIs) and the SFP-only module ports
are network node interfaces (NNIs).
If the switch is running the metro IP access image, you can configure any number of ports as NNIs. If
the switch is running the metro base or metro access image, you can configure only four ports as NNIs.
When running these images on an ME 3400-12CS switch, if you want to configure a dual-purpose port
as an NNI, you must first change the port type of an SFP-only module port to UNI by entering the
port-type uni interface configuration command so as not to exceed the switch maximum of four NNIs.
By default, the switch dynamically selects the dual-purpose port media 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. In auto-select mode, the switch gives preference to SFP mode if both copper
and fiber-optic signals are simultaneously detected.
Beginning in privileged EXEC mode, follow these steps to select which dual-purpose media type to
activate. This procedure is optional.
Command
Step 1 configure terminal
Step 2
interface interface-id
Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
9-18
Purpose
Enter global configuration mode.
Specify the dual-purpose port to be configured, and enter interface
configuration mode.
Chapter 9 Configuring Interfaces
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