I
NTERFACE
C
OMMANDS
25-4
Default Setting
Auto-negotiation is permanently disabled on Ports 1-16, and enabled
by default on Ports 17-19.
When auto-negotiation is disabled, the default speed-duplex setting is:
- Fast Ethernet ports – 100full (100 Mbps full-duplex)
- Gigabit Ethernet ports – 1000full (1 Gbps full-duplex)
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
1000BASE-T does not support forced mode. Auto-negotiation
should always be used to establish a connection over any
1000BASE-T port or trunk.
To force operation to the speed and duplex mode specified in a
speed-duplex command, use the no negotiation command to
disable auto-negotiation on the selected interface.
When using the negotiation command to enable auto-negotiation,
the optimal settings will be determined by the capabilities command.
To set the speed/duplex mode under auto-negotiation, the required
mode must be specified in the capabilities list for an interface.
Example
The following example configures port 5 to 100 Mbps, half-duplex
operation.
Related Commands
negotiation (25-5)
capabilities (25-6)
Console(config)#interface ethernet 1/5
Console(config-if)#speed-duplex 100half
Console(config-if)#no negotiation
Console(config-if)#