do anyone know how is it possible to find out unused vlans even from trunk ports ?
the output of SHOW INTERFACE TRUNK on your switch will show the vlans that are active and forwarding on a given trunk.... does that help?
it will show up too many vlans , I just found the answer , :
--show mac-address-table vlan X
You could also just sh vlan on the switch, or you could setup VTP pruning if you are using VTP.
Show Vlan Brief, would have listed your vlans and you would have noticed what ports arent tagged those unused vlans.