It looks like you may need to issue the switchport and no shut commands on the physical interface. [URL] 
When trying to configure a port in a layer-3 VLAN we get the error "Port is not in layer-2 mode". Reading the documentation regarding layer-3 VLANs everything seems pretty straight forward, but we can't get it to work. We have following configuration: interface TenGigabitEthernet 1/5no ip addressshutdown! interface Vlan 2name managementip address "ip-address" /24no shutdown! Next we try configure terminalinterface vlan2untagged TenGigabitEthernet 1/5 Error: Port is not in Layer-2 mode Te 1/5 But it's layer-3, so the port shouldn't be in layer-2 mode. Are any other configuration steps needed? Or has anyone expercience with this error? Best regards, Sven Vanwalleghem
Force 10 "Port is not in layer-2 mode"