Use the switchport nonegotiate interface configuration command to specify that Dynamic Trunking Protocol (DTP) negotiation packets are not sent on the Layer 2 interface. The switch does not engage in DTP negotiation on this interface. Use the no form of this command to return to the default setting.
no switchport nonegotiate
This command has no arguments or keywords.
The default is to use DTP negotiation to determine trunking status.
The no form of the switchport nonegotiate command removes nonegotiate status.
This command is valid only when the interface switchport mode is access or trunk (configured by using the switchport mode access or the switchport mode trunk interface configuration command). This command returns an error if you attempt to execute it in dynamic (auto or desirable) mode.
Internetworking devices that do not support DTP might forward DTP frames improperly and cause misconfigurations. To avoid this, you should turn off DTP by using the switchport nonegotiate command to configure the interfaces connected to devices that do not support DTP to not forward DTP frames.
When you enter the switchport nonegotiate command, DTP negotiation packets are not sent on the interface. The device does or does not trunk according to the mode parameter: access or trunk.
?If you do not intend to trunk across those links, use the switchport mode access interface configuration command to disable trunking.
?To enable trunking on a device that does not support DTP, use the switchport mode trunk and switchport nonegotiate interface configuration commands to cause the interface to become a trunk but to not generate DTP frames.
This example shows how to cause a port interface to refrain from negotiating trunking mode and to act as a trunk or access port (depending on the mode set):
Switch(config-if)# switchport nonegotiate
You can verify your setting by entering the show interfaces interface-id switchport privileged EXEC command.
Displays the administrative and operational status of a switching (nonrouting) port, including port blocking and port protection settings.
Configures the VLAN membership mode of a port.