Chapter 7 Configuring Gigabit Ethernet Interfaces

Configuring a Combo Port

 

Command

Purpose

Step 1

 

 

configure terminal

Enter global configuration mode.

 

Example:

 

 

Router# configure terminal

 

Step 2

 

 

mac-flap-ctrl on per-mac <mac-movement>

Enable MAC flap control.

 

<time-interval>

mac-movement—Maximum number of MAC movements

 

 

 

 

 

 

that are allowed in the specified time.

 

Example:

time-interval—Time interval that can elapse before the MAC

 

Router(config)# mac-flap-ctrl on per-mac

movements are tagged as flapping.

 

20

10

 

 

 

 

If values are not specified for the above parameters, the default

 

 

 

values are taken by the router. The default values for the counters

 

 

 

are five and ten; that is five movements in ten seconds.

 

 

 

The no form of the command disables this feature.

 

 

 

 

Configuring a Combo Port

A combo port is considered as a single interface with dual front ends (an RJ-45 connector and an SFP module connector). The dual front ends of a combo port are non-redundant interfaces; the

Cisco ASR 901 router activates only one connector of the pair. Combo ports can be configured as copper ports or small form-factor pluggable (SFP) module ports.

By default, the Cisco ASR 901 router selects the RJ-45 connector. However, you can use the media-typecommand to manually select the media type. When the media type is auto-select, the router gives preference to SFP module if both copper and fiber-optic signals are simultaneously detected.

Restrictions

When you configure SFP or RJ-45 media type, the non-configured media type is disabled even if there is a connector installed on the interface and no connector on the configured media type.

When the media type is auto-select, the Cisco ASR 901 router configures both types with auto negotiation of speed and duplex.

When the media type is auto-select, you cannot use 100M SFPs.

When the media type is auto-select, you cannot use the speed and duplex commands.

When the media type is auto-select, the Cisco ASR 901 router uses the following criteria to select the type:

If only one connector is installed, that interface is active and remains active until the media is removed or the router is reloaded.

If both media are installed in the combo port, the router gives preference to the SFP module interface.

If both media are installed in the combo port, when the SFP module interface is inactive, the RJ-45 connector is selected. When the SFP module interface recovers and becomes active, the RJ-45 connector is disabled and the router gives preference to the SFP module interface.

Cisco ASR 901 Series Aggregation Services Router Software Configuration Guide

7-6

OL-23826-09

 

 

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Cisco Systems A9014CFD manual Configuring a Combo Port, Restrictions, Mac-flap-ctrl on per-mac mac-movement, Time-interval