4-5
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide—Release 8.2GLX
78-15908-01
Chapter 4 Configuring Ethernet and Fast Ethernet Switching
Configuring Ethernet and Fast Ethernet Ports
Caution
Make sure that the device on the other end of the link is also configured for autonegotiation, or a port
speed or duplex mismatch will result.
Note
If the port speed is set to auto on a 10/100-Mbps Fast Ethernet port, both speed and duplex are
autonegotiated.
To set the port speed for a 10/100-Mbps port, perform this task in privileged mode:
This example shows how to set the port speed to 100 Mbps on port 2/2:
Console> (enable) set port speed 2/2 100
Port 2/2 speed set to 100 Mbps.
Console> (enable)
This example shows how to make port 2/1 autonegotiate speed and duplex with the neighbor port:
Console> (enable) set port speed 2/1 auto
Port 2/1 speed set to auto-sensing mode.
Console> (enable)
Setting Ethernet and Fast Ethernet Port Duplex Modes
You can set the port duplex mode to full or half duplex for Ethernet and Fast Ethernet ports.
Note
If the port speed is set to auto on a 10/100-Mbps Fast Ethernet port, both speed and duplex are
autonegotiated. You cannot change the duplex mode of ports that are configured for autonegotiation. For
information on enabling and disabling autonegotiation on 10/100 Fast Ethernet ports, see the
“Setting
Ethernet and Fast Ethernet Port Speeds” section on page 4-4
.
To set the duplex mode of a port, perform this task in privileged mode:
This example shows how to set the duplex mode to half duplex on port 2/1:
Console> (enable) set port duplex 2/1 half
Port 2/1 set to half-duplex.
Console> (enable)
Task
Command
Step 1
Set the port speed of a 10/100-Mbps Fast Ethernet
port.
set port speed mod num/port num {10 | 100 |
auto}
Step 2
Verify that the speed of the port is configured
correctly.
show port [mod_num [/port_num]]
Task
Command
Step 1
Set the duplex mode of a port.
set port duplex mod num/port num {full | half}
Step 2
Verify that the duplex mode of the port is
configured correctly.
show port [mod_num [/port_num]]