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New Member

Managing Cisco 1242s with 2 VLANs

Hello- I am tasked with building out an autonomous AP system with surplus 1242s (AIR-AP-1242AG-A-K9). The topology would be:

LAN (trunk) -- AP -- (Bridge) -- AP Fa0 -- PC NIC

I need to provide a layer 2 VLAN access to a PC attached directly to the Ethernet interface (vendor controls layer 3 addressing). And I need to be able to manage the APs from an existing layer 3 management VLAN. DISCLAIMER: I am not a wireless guy.

That said, in my (confused) reading I have formulated a plan to use interface BVI1 as management, create an interface off one of the radios:

interface Dot11Radio0.VLANID

encapsulation dot1Q VLANID native

And then trunk the root-side switchport.

Feasible? Way off base? (Better) suggestion?


New Member

Managing Cisco 1242s with 2 VLANs

In building this scenario, I ran into a DOH! moment -- where is the other side of the trunk? The Fa0 interface on the AP cannot be trunked (I think). However, some success: when I tagged frames in VLANID on the switch-side trunk with native VLAN VLANID (OK, that is getting old, let's call L2 VLAN 500 and mgt VLAN 50). So when I set native VLAN to 500 on the switch port I was able to ping the PC NIC.

VLAN 500, ping >-- trunk -- AP -- (bridge) -- AP -- > ping success PC NIC

Now the issue is how do I get VLAN 50 across?

New Member

Managing Cisco 1242s with 2 VLANs

I realize I should have said UNtagged the frames on the trunk, but you get the idea.

It is seeming like I am only able to pass one VLAN over this topology. Anyone have any other ideas?

New Member

Managing Cisco 1242s with 2 VLANs

Any replies at all would be helpful at this point...

Managing Cisco 1242s with 2 VLANs

You've been going at this for a while.

Okay, so the AP should be configured with subinterfaces for all of the related vlans. You would encapsulate all vlans once you configure subinterfaces, or the native vlan no longer works. In the following example, I'll use 2 vlans:

int d0

ssid TEST

ssid TEST-2

encryption vlan 1 ciphers tkip

encryption vlan 2 ciphers tkip

int d0.1

encapsulate dot1q 1 native

bridge-group 1

int d0.2

encapsulate dot1q 2

bridge-group 2

int fa0.1

encapsulate dot1q 1 native

int fa0.2

encapsulate dot1q 2

int bvi1

ip address

On your vlans, you would need something on the other end routing for them, so you would need a L3 switch or a router.


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HTH, John *** Please rate all useful posts ***
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