In interface configuration mode, use the 'phy' setting.
CSS(config-if[ 2/2])# phy ?
100Mbits-FD 10/100 ports only. Set to 100 Mbits/s, Full-Duplex
100Mbits-HD 10/100 ports only. Set to 100 Mbits/s, Half-Duplex
10Mbits-FD 10/100 ports only. Set to 10 Mbits/s, Full-Duplex
10Mbits-HD 10/100 ports only. Set to 10 Mbits/s, Half-Duplex
1Gbits-FD-asym Gigabit ports only. Set to Full duplex with asymmetric
pause toward link partner
1Gbits-FD-no-pause Gigabit ports only. Set to Full duplex with no pause
1Gbits-FD-sym Gigabit ports only. Set to Full duplex with symmetric
pause
1Gbits-FD-sym-asym Gigabit ports only. Set to Full duplex with symmetric and
asymmetric pause toward local device
auto-negotiate Allow the interface to auto-negotiate speed and duplex
mode.
