Interface Speed and Duplex

14-04+Speed+and+Duplex+Settings.pdf

Interface speed and duplex is set to "auto" by default

Both sides of a link should auto negotiate to full duplex and the fastest available speed

Best practice is to set manually set speed and duplex on ports

It is very important to set matching speed and duplex settings on both sides of the link

Commands

SW1 (config) # inteface FastEthernet 0/1 SW1 (config-if) # duplex full SW1 (config-if) # speed 100

Verification Commands

SW1 # show running-configuration SW1 # show ip inteface breif SW1 # show run interface vlan 1 SW1 # show interface vlan 1 SW1 # show version (ios version)