A nice command if you want to confirm that DTP is or is not working on an interface. On SW1 I used switchport nonegotiate command. On SW2 (connected to SW3) I used switchport mode dynamic auto.
A nice command if you want to confirm that DTP is or is not working on an interface. On SW1 I used switchport nonegotiate command. On SW2 (connected to SW3) I used switchport mode dynamic auto.