Flow Control Capabilities; Speed/Duplex Settings For The Gigabit Ethernet Ports - Cisco 2800 Series Manual

The following is a typical show running config command output for gig 0/0:
router# show run int gigabitEthernet 0/0
Building configuration...
Current configuration : 156 bytes
!
interface GigabitEthernet0/0
no ip address
load-interval 30
shutdown
duplex auto
speed auto
media-type sfp
no cdp enable
end

Flow Control Capabilities

Both the RJ-45 (copper) and SFP (fiber) modes of operations suppot flow control. This means that
during congestion conditions, pause frames are sent to the far end by the Media Access Control (MAC)
hardware. Also, the MAC hardware will react to the pause frames received. There is no way in current
MAC hardware to track the number of pause frames received or sent.
Flow control is on by default
Currently, there is no command to turn off the flow control capability for any of the Gigabit Ethernet
ports in any of the RJ45 or SFP modes.

Speed/Duplex Settings for the Gigabit Ethernet Ports

Typically, speed and/or duplex communications are configured manually using the speed and/or duplex
CLI commands.
For the SFP port, the speed settings can be set to 1000 Mbps or auto only, and duplex can be set to full
Note
or auto only.
The following examples show the available options:
interface gigabitEthernet 0/[0-1]
router(config-if)# speed ?
10
100
1000
auto
router(config-if)# duplex ?
auto
full
half
OL-5992-01
Force 10 Mbps operation
Force 100 Mbps operation
Force 1000 Mbps operation
Enable AUTO speed configuration
Enable AUTO duplex configuration
Force full duplex operation
Force half-duplex operation
Examples of Using the Setup Command Facility to Configure Interface Parameters
Basic Software Configuration Using the Setup Command Facility
7