12-17
Cisco IE 3010 Switch Software Configuration Guide
OL-23145-01
Chapter 12 Configuring Interface Characteristics
Configuring Ethernet Interfaces
These sections describe how to configure the interface speed and duplex mode:
• Speed and Duplex Configuration Guidelines, page 12-17
• Setting the Interface Speed and Duplex Parameters, page 12-17
Speed and Duplex Configuration Guidelines
When configuring an interface speed and duplex mode, note these guidelines:
• Fast Ethernet (10/100-Mb/s) ports support all speed and duplex options.
• Gigabit Ethernet (10/100/1000-Mb/s) ports support all speed options and all duplex options (auto,
half, and full). However, Gigabit Ethernet ports operating at 1000 Mb/s do not support half-duplex
mode.
• For SFP module ports, the speed and duplex CLI options change depending on the SFP module type:
–
The 1000BASE-x (where -x is -BX, -CWDM, -LX, -SX, and -ZX) SFP module ports support
the nonegotiate keyword in the speed interface configuration command. Duplex options are not
supported.
–
The 1000BASE-T SFP module ports support the same speed and duplex options as the
10/100/1000-Mb/s ports.
–
The 100BASE-x (where -x is -BX, -CWDM, -LX, -SX, and -ZX) SFP module ports support only
100 Mb/s. These modules support full- and half- duplex opti ons but do not support
autonegotiation.
For information about which SFP modules are supported on your switch, see the product
release notes.
• If both ends of the line support autonegotiation, we highly recommend the default setting of auto
negotiation.
• If one interface supports autonegotiation and the other end does not, configure duplex and speed on
both interfaces; do not use the auto setting on the supported side.
• When STP is enabled and a port is reconfigured, the switch can take up to 30 seconds to check for
loops. The port LED is amber while STP reconfigures.
Caution Changing the interface speed and duplex mode configuration might shut down and re-enable the
interface during the reconfiguration.
Setting the Interface Speed and Duplex Parameters
Beginning in priv ileged EXEC mod e, follow these steps to set the speed and duplex mode for a physical
interface:
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Specify the physical interface to be configured, and enter interface
configuration mode.