802.1q Trunking
Change the trunking encapsulation on SW1’s inter-switch links from static ISL to static 802.1q.
SW1(config)#int range Fa0/13 - 21 SW1(config-if-range)#switchport trunk encapsulation dot1q
Verify that SW2, SW3, & SW4 are negotiating 802.1q as the trunking encapsulation to SW1, and that SW1 is not negotiating 802.1q to SW2, SW3, and SW4
SW1#sh int trunk Port Mode Encapsulation Status Native vlan Fa0/13 desirable 802.1q trunking 1 Fa0/14 desirable 802.1q trunking 1 Fa0/15 desirable 802.1q trunking 1 Fa0/16 desirable 802.1q trunking 1 Fa0/17 desirable 802.1q trunking 1 Fa0/18 desirable 802.1q trunking 1 Fa0/19 desirable 802.1q trunking 1 Fa0/20 desirable 802.1q trunking 1 Fa0/21 desirable 802.1q trunking 1
SW2#sh int trunk Port Mode Encapsulation Status Native vlan Fa0/6 on 802.1q trunking 1 Fa0/13 auto n-802.1q trunking 1 Fa0/14 auto n-802.1q trunking 1 Fa0/15 auto n-802.1q trunking 1
SW3#sh int trunk Port Mode Encapsulation Status Native vlan Fa0/13 auto n-802.1q trunking 1 Fa0/14 auto n-802.1q trunking 1 Fa0/15 auto n-802.1q trunking 1
SW4#sh int trunk Port Mode Encapsulation Status Native vlan Fa0/13 auto n-802.1q trunking 1 Fa0/14 auto n-802.1q trunking 1 Fa0/15 auto n-802.1q trunking 1
Categories: IT, Networking, Switching