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New Member

DHCP issues

I cannot get my Aironet to pull a DHCP address using VLANS. If I debug on the Aironet, I do not even see DHCP request packets. I was under the impression that it would pull this automatically. I have 3 VLANS on the Aironet, a Dot1Q trunk to my switch, 3 Vlan interfaces on the switch and then helper-addresses on the Vlan interfaces pointing to my DHCP server. If I use static addressing on my clients, I have full connectivity. What am I missing??

  • Other Wireless - Mobility Subjects
New Member

Re: DHCP issues

If I can assume that you have a Access Point not a combo AP/Router I have had a similar issue.

I cannot understand, though, how the access point can utilise an IP helper command anyway. Forgive me if I am wrong, but the AP is a Layer 2 device (bridge) and therefore I can't see any way that it can get involved in DHCP (A layer 3 protocol). I notice that it is spoken about in the IOS notes, but I still don't understand how it works.

You are best making sure that you either have a DHCP server on each VLAN or configuring the IP Helper command on the VLAN interface of the router.