Client unable to get DHCP address over wireless bridge

[phil6564]

Hi all

I setup a wireless bridge between two Extreme AP305 access points, one connected to a switch on the live network and the other to a standalone switch. I configured an access port on the standalone switch and plugged a laptop into it to test connectivity over the bridge. I found that if I put a static ip address on the laptop it is able to connect to the live network, proving that the wireless bridge is functional, but if set to DHCP it is unable to get an ip address. We can see the DHCP requests reaching the AP on the live network side. 

Is there any further AP configuration required, to forward on the DHCP requests maybe, or is there some further config required in DHCP? Or does anyone have any suggestions as to what else could be causing the problem?

Thanks in advance,

Phil.

[phil6564 · Accepted solution]

Hi Sam.

It turned out to be the “ip dhcp snooping trust” command that was missing.

Thanks for the reply anyway.

Regards,

Phil.

[SamPirok]

Hi Phil, if you’re using a DHCP server on your network, the only thing the AP should need is access to the VLAN the DHCP server is using. If you’re setting up a DHCP server on an AP, this guide reviews the configuration needed for that. 

If the DHCP server is hosted on your network, I’d run a VLAN probe to make sure we can get traffic there and back on that VLAN. The command for a VLAN probe is: 

int mgt0 dhcp-probe vlan-range # #

If you want to run a range of VLANs for the VLAN probe, VLAN 1 through VLAN 5 for example, you would enter 1 5 where you see the # signs. If you want to test one VLAN at a time, VLAN 5 for example, you would just do 5 5 where you see the # signs. So if I was running a VLAN probe for VLAN 5, the command would be “int mgt0 dhcp-probe vlan-range 5 5”.