Regarding the vlan setup for the WLC

[diwakar410]

I am supposed to configure VLAN in router and switch for WLC deployment. Then while doing the study i found this article on internet: 

Now the way the guy has configured vlan in router has confused me. I was thinking of configuring the subinterfaces on the router and then assigning dot1q tag to it according to the vlan.

I would use this:

interface fa 0/3.10 

ip address 10.1.1.1 255.255.255.0

no shut

similarly, interface fa0/3.20

ip add 20.1.1.1 255.255.255.0

and do the route and NAT thing.But the guy has done it in different way. The guy is surely right but can it be done according to what i have listed above?

Thanks in advance.

[johnd2310 · Accepted solution]

Hi,

Yes, you can do it your way. You will need to add the encapsulation dot1Q command on each sub-interface.

interface fa 0/3.10
ip address 10.1.1.1 255.255.255.0
encapsulation dot1Q 10

interface fa0/3.20
ip add 20.1.1.1 255.255.255.0
encapsulation dot1Q 20

Thanks

John

[paul driver · Accepted solution]

Hello

Yes it can, The way you suggested is some-times call "router on a stick" routing in which having sub interface on the rtr to route between to vlans.

The other way from the article you posted shows the router performing inter-vlan routing with Switch Virtual interfaces (SVI's).

This way he has create 3 SVI's:

Vlan1 = MGT vlan between the switch and the ISP rtrs LAN facing interface
Vlan 10/20 -  WLAN vlans ( for WAP and WLC connections)

The connection between the RTR and Switch is trunked to allow tagged traffic to traverse between either other

The connection to the isp is an access port in vlan 1

From the switch perspective, it just a host switch configured with two layer vlans 10,20 and a default-gateway pointing to the what looks like the ISP rtrs lan facing interface
 ( I personally would point the switch to the 887 rtr vlan 1 svi 192.168.0.202 as it has a default route point the the isp anyway.

The WLC and the Access-point connections are just access ports in there respective vlans.

The Nating speaks for it self, However not sure why he performing this as the current MGT addressing suggests the ISP is already doing this.

That's it...

res

Paul

[diwakar410]

Hi Paul,

I think the connection to the WLC should be trunk and in the figure as well the guy has done it trunk. Trunk in a sense that it has to carry multiple vlans as well. I mean there are vlans 1,10, 20 and for it to understand which tag it is carrying, i think the switchport connecting to the WLC should be trunk. Please clearify if i am wrong.