allowing vlans in trunk

[vishalpatil86]

hi,

i have configured switch 2960 with gig0/1 trunk port..

when i type cmd sh int gig0/1 trunk, it shows me following -

sw#sh int gig 0/1 trunk

Port        Mode             Encapsulation  Status        Native vlan

Gi0/1       on               802.1q         other         10

Port        Vlans allowed on trunk

Gi0/1       none

Port        Vlans allowed and active in management domain

Gi0/1       none

Port        Vlans in spanning tree forwarding state and not pruned

Gi0/1       none

how come it is not showing allowed vlans? kindly suggest.

[johnlloyd_13]

Hi Vishal,

You would need to manually add those vlans.

Switch(config-if)#switchport trunk allowed vlan

Make a show run int gig0/1 or do a show int gig0/1 switchport to see the results.

Sent from Cisco Technical Support iPhone App

[fabio.marino]

Hi Vishal, in order to see allowed vlan on your switch is enough to use the "show interface trunk" command. In this way you can see the allowed vlan for each port of your switch.

[Antonio Knox · Accepted solution]

If this is a fresh configuration, and the interface is not up and connected to a trunking switch, this is what you will see in the output until you connect it to a switch that will bring up the trunk.  Follow the basic rules of trunking between the switches (switchport, switchport mode, encapsulation and native vlan) and you should see the trunking info.

[vishalpatil86]

thanx antonio, i agree with u.....its perfectly correct.