how to setup a trunk port on cisco switch

A trunk port can have two or more VLANs configured on the interface; it can carry traffic for several VLANs simultaneously while the access port can only carry traffic for one VLAN. To configure a Trunk Port for port that connects to another switch, use the instructions below: switch# configure terminal switch(config)# interface gigabitEthernet 1/0/48 switch(config-if)# switchport mode trunk Setup a either ISL or IEEE 802.1Q VLAN protocol on your trunk port. ISL is a Cisco-proprietary trunking protocol, making it unsuitable for a multi-vendor environment, which makes IEEE 802.1Q the common VTP protocol. Setup 802dot1Q on your trunking ports: switch# configure terminal switch(config)# interface gigabitEthernet 1/0/48 switch(config-if)# switchport trunk encapsulation dot1q Allow all VLANs to pass trhough your trank ports: switch# configure terminal switch(config)# interface gigabitEthernet 1/0/48 switch(config-if)# switchport trunk allow vlan all