show vlan (Cisco)

show vlan lists the Vlans and the ports on which each is configured. Trunk ports don't show up in this list.

Vlans 1002, 1003, 1004 and 1005

In the output of the show vlan command, Vlans 1002, 1003, 1004 and 1005 are listed. Those exist by default to ensure interoperation and backwards compatibility of new devices with old and largely deprecated networks. For example, Vlans 1002 and 1004 were used on an old fiber optics type of network, whereas Vlan 1003 was used in token-ring networks. In the status column, those networks show up as either act/unsup or active/unsupported, since most new switches don't even have ports to use on those old types of networks any more.

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