Configuring Trunk on cisco switches (non-negotiated vs negotiated option)

[zafar_118]

Hello,

Will the trunk come up if the port on one switch is hard coded as trunk with non-negotiated option (no DTP frames)with another switch having the interface configured as trunk with negotiated (DTP frames enabled)          

Thanks

[Peter Paluch]

Hi,

If both ports are hardcoded as trunks, just one has DTP active and the other has DTP deactivated, the trunk will come up.

Best regards,

Peter

[zafar_118]

Hi Peter,

Thanks for the reply.

If DTP packets are not used in bringing up a trunk then what exactly is their use i.e. if i have trunk in non negotiate on one side and dynamic auto on other, i assume that trunk will never come up.

[devils_advocate]

DTP packets are used to negotiate a trunk but by using the nonegotiate command, you are telling the switch port to no longer send the DTP packets, meaning you have to statically configure a trunk port if you want one.

In my experience if you want a trunk, staitcally configure it at both ends.