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3560 using 802.1q to 1841 routing question

4402 Wireless Controller (p1 to 24P G0/2)

3560- 24 port POE (G0/1 to 48P G0/2)

3560-48Port (G0/1 to 1841 F0/0)

Cisco 1841 router (F0/1 to core net)

The 4402 uses 3 dot1q vlans. I want to use the 1841 to route between the vlans as the 1841 has a firewall which is a requirement that must be used in this design. I thought I could use dot1q on the gi0/x interfaces up to the router and then utilize the firewall on the router to route traffic between the VLANS. I configured the wireless network without the router and everything works fine. I remove all the int vlan entries, install the dot1q encapsulation on the G0/x ints, create the 1841 subinterfaces and NO GO. I could be way off base on how I think this should work and since it DOESN'T work I'm looking forward to any assistance you can provide.

3560 Switches

48 port - G0/1 and G0/2

switchport trunk encapsulation dot1q

switchport mode dynamic desirable

24 port -


switchport trunk encapsulation dot1q

switchport mode dynamic desirable

g0/2 Wireless 4402

switchport trunk encapsulation dot1q

switchport mode trunk

Cisco 1840 with K9-Sec Image

created sub intefaces on 1841 int f0/0

assigned dot1q vlan to each sub int

assigned ip address to each sub int


int f0/0.5

encaspulation dot1Q 3

ip address

ip helper-address

When I run a trace on the 24P G0/2 I can see an arp request go out when I attempt to ping from the wireless controller console and thats it. Your help is greatly appreciated!

Note: I have attached the configs for your viewing pleasure.




Re: 3560 using 802.1q to 1841 routing question

Hey there Scott,

As a test, create 2 vlans on the switch, don't have it routing and connect it to the 1841.

Put a PC in each of the vlans and get a ping going, using the 1841 for intervlan routing.

Then build it up from there.

Let me know how it goes!



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