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Command mode:
Port Mode.
Default:
The default setting for combo mode of combo ports is sfp-preferred-auto.
Usage Guide:
The combo mode of combo ports and the port connection condition determines the active port of the combo ports. A
combo port consists of one fiber port and a copper cable port. It should be noted that the speed-duplex command
applies to the copper cable port while the negotiation command applies to the fiber cable port, they should not
conflict. For combo ports, only one, a fiber cable port or a copper cable port, can be active at a time, and only this
port can send and receive data normally. For the determination of the active port in a combo port, see the table below.
The headline row in the table indicates the combo mode of the combo port, while the first column indicates the
connection conditions of the combo port, in which
Note:
1. Combo port is a conception involving the physical layer and the LLC sublayer of the datalink layer. The status of a
combo port will not affect any operation in the MAC sublayer of the datalink layer and upper layers. If the bandwidth
limit for a combo port is 1Mbps, then this 1Mbps applies to the active port of this combo port, regardless of the port
type being copper or fiber.
2. If a combo port connects to another combo port, it is recommended for both parties to use the forced copper or the
forced fiber mode.
3. Run show interface under Admin Mode to check for the active port of a combo port .The following result indicates if
the active port for a combo port is the fiber (or copper) cable port: Hardware is Gigabit-combo, active is fiber (or
copper)
Example:
Setting ports 1/21-24 to the forced fiber mode.
Switch(config)#interface ethernet 1/21-24
Switch(Config-Port-Range)#media-type fiber
4.1.9 negotiation
Command:
negotiation {on | off}
Function:
Enables/Disables the auto-negotiation function of a 1000Base-FX port.