23
Change the Media Type of the Native Gigabit Ethernet SFP GBIC or RJ-45 Ports
To be able to use a particular media port, use CiscoIOS to select the media type. This is done by using the media-type interface
command:
media-type { gbic | rj45 }
Example:
interface GigabitEthernet 0/1
media-type rj45
end
Configure the Interface Transmission and Speed Modes
Step 1 After changing the media type, configure the speed and transmission modes to appropriately match the new interface
characteristics. Changing the speed and duplex of a Cisco 7301 router Gigabit Ethernet interface is done using the speed
and duplex interface commands.
Note These commands are only applicable when using the RJ-45 media.
speed { 10 | 100 | 1000 | auto }
duplex { full | half | auto }
The following speed/duplex settings are supported:
Media Type Speed Duplex
-------------------------------------------------------
RJ45 10, 100, 1000, auto full, half, auto
GBIC(1) 1000, auto(2) full, half, auto
-------------------------------------------------------
a. If you are using the no negotiation auto command, the speed and duplex should be set to a value other than auto for
correct operation.
b. The only available speed in this mode is 1000 Mbps; there is no difference whether 1000 or auto is selected.
When using the SFP GBIC media, there is also the additional negotiation auto command that is used to enable the IEEE 802.1z
Gigabit Ethernet (1000 Mbps) autonegotiation protocol.
Step 2 To tu rn t he negotiation auto feature off (it is on by default), issue the interface command no negotiation auto. This is
useful for connecting to other Gigabit Ethernet equipment that does not support 802.1z autonegotiation.
Note The negotiation auto feature is not supported when using the media type rj-45 and will be ignored if implementation
is attempted.
The media-type gbic mode will always default to 1000 Mbps. Both full-duplex and half-duplex operation are supported in this
mode.