Multiple Vlans on a single port.

[vishal.divekar]

hi,

Can i configure single port with multiple vlans on L2 2950 switch, if yes then what are the commands.

Thanks,

Vishal D.

[pkhatri]

Vishal,

You can indeed. A port with multiple VLANs is called a trunk interface and carries 802.1q or ISL-tagged traffic. The command to make a port a trunk is 'switchport mode trunk'

Hope that helps - pls rate the post if it does.

Paresh

[vishal.divekar]

Paresh,

i think i have not quoted the question properly.

see by doing 'switchport mode trunk' it will flow the traffic of all vlan right.

but if i want to give access of selected vlans then what to do,

i have tried the command 'switchport trunk allowed vlan 1,2,3'

do i have to give encapsulation on that port, but on 2950 encap cannot be configured.

now can u tell me wht is possible to do.

Thanks for ur reply.

Vishal.

[pkhatri]

Hi Vishal,

What sort of encap do you want to use on the trunk - 802.1q ? AFAIk, the 2950 does not support ISL, so the only option is 802.1q, which is enabled by default. Therefore, you do not need to configure any encapsulation and the 'switchport trunk allowed vlan 1,2,3' will limit your VLANs on the trunk appropriately.

Hope that helps - pls rate the post if it does.

Paresh

[williamwbishop]

Perhaps a better way might be to go with:

(config-if)#switchport trunk allowed vlan remove 2-1001

(config-if)#switchport trunk allowed vlan add 2,3,4

[vishal.divekar]

William,

Thanks for ur suggestion,

i tried the commands u said but the problem i face is when i do sh vlan it doesn't show the interface can u tell me why it is not visible.

waiting for ur reply,

Thanks,

Vishal.

[pkhatri]

Hi Visha,

The 'sh vlan' command will only show information for access-ports. Use the 'sh interface trunk' command to get information on trunks...

Hope that helps - pls rate the post if it does.

Paresh