topic Re: Option 43 Not working in Wireless

Option 43 Not working

mlarnell210 — Mon, 05 Jul 2021 16:20:39 GMT

I have dhcp built on the core router with option 43 and hex. Once I connected an ap to the new vlan the ip helpers do not work. The ap does get an ip address. If i put the ap on another wireless vlan it works. All wireless vlans are built the same. I am going to connected an ap and get a log file of where the ap gets stuck at. In the mean time any help is appreciated

Re: Option 43 Not working

balaji.bandi — Mon, 22 Oct 2018 20:23:41 GMT

i always compare the configuration with working one.

and enable some debug and see what is wrong..

give more information what is the AP models you having issue ? what is the VLAN config working vs Not working.

if possible post both the configurations.

Re: Option 43 Not working

Leo Laohoo — Mon, 22 Oct 2018 22:42:02 GMT

@mlarnell210 wrote:

Once I connected an ap to the new vlan the ip helpers do not work. The ap does get an ip address. If i put the ap on another wireless vlan it works. All wireless vlans are built the same.

So the AP gets a valid IP address when it's on the new VLAN but cannot get the WLC information from DHCP Option 43?

When this happens what is the behaviour of the AP? Does it "wait" for the WLC controller or does it immediately "know" of a controller?

Can you post the new DHCP Option 43 HEX?

Re: Option 43 Not working

pieterh — Tue, 23 Oct 2018 12:48:55 GMT

the ip helpers do not work. The ap does get an ip address.

-> this has nothing to do with dhcp option-43

option-43 is for finding the wireless controller, not for finding a dhcp-server

of course the AP needs an IP-address first, before it can connect to the WLC using tcp/ip.

if you connect a workstation to the same switchport, does that get an ip-address?

Re: Option 43 Not working

balaji.bandi — Tue, 23 Oct 2018 13:08:00 GMT

Make sure the VLAN have reach-ability to DHCP Server? have you checked and compared the config as suggested ?