MR 44 wifi clients are not getting IP address from Window server DHCP

lcollado
Comes here often

MR 44 wifi clients are not getting IP address from Window server DHCP

I'm replacing my old cisco wifi AP's with MR 44.  the old cisco AP's wifi clients get their IP address form the DHCP.  I notice we have some DHCP options in the scope for wifi clients to get assigned a specific subnet. 

I have plugged  12 Meraki AP and the AP's themselves get an assigned IP from the windows dhcp but the wifi clients do not.  could the old cisco DHCP options be preventing the Meraki wifi clients from getting an IP address?

 

scope opitions on the windows DHCP Options are 241, 43 and 103

11 REPLIES 11
BrandonS
Kind of a big deal

It sounds like the SSID is not in bridged mode. You need that for external (from the AP) DHCP to function with clients. 

- Ex community all-star (⌐⊙_⊙)

Hi Brandon, I'm sorry I forgot to mention.  I have the SSID set to bridge mode.  I have configured the port the AP's are connected to trunk ports adding the vlan of where the dhcp server resides on.  I'm able to authenticate to the Radius server but don't get an IP address.

ww
Kind of a big deal
Kind of a big deal

Does the svi from that client vlan has a dhcp relay/helper to your dhcp server

lcollado
Comes here often

Hello @ww , I'm not sure how to check, is there a command I can run on the switch?

ww
Kind of a big deal
Kind of a big deal

On the switch that has the svi for that vlan. It should have a "ip helper" on the svi. (Asuming you have a cisco catalyst)

you should be able to see it running:

Show run int vlan <NUMBER>

 

https://www.cisco.com/en/US/docs/ios/12_4t/ip_addr/configuration/guide/htdhcpre.html

lcollado
Comes here often

Hello @ww can you provide some guidance on how to configure SVI and should I only configure it on the Port that the AP is connected on?

Ryan_Miles
Meraki Employee
Meraki Employee

This rule needs to say allow for local LAN

 

Screenshot 2023-01-23 at 19.52.30.png

@Ryan , thank you for your suggestion for this.  I check this option and it allows for access to other networks in the WLAN outside my on-prem networks but using the Meraki AP assigned NAT mode which assigns IP addresses to the client in the 10.0.0.0/8 network.  which could overlap with other networks in our global MPLS.  not sure

GIdenJoe
Kind of a big deal
Kind of a big deal

If you used to use a Cisco AireOS based controller, chances are that you were using DHCP proxy mode in which the controller relays the DHCP requests to the server.  In that case you wouldn't have needed a DHCP relay on the default gateway in your LAN where the client is at.
Please check as @ww said that you have dhcp relay (helper address) configured on all the interfaces of your gateway device that routes these subnets.

I did notice the AireOS controllers are pointing to my internal DHCP server.  when I run ipconfig on a client connected to the old AP's it states the DCHP server as 1.1.1.1 which is associated with the AP controller.

now I have configured the port on the switch in which the Meraki AP is connected to a trunk and added the VLAN allowed in which my internal DHCP resides and the wireless vlan. which I also noticed it's tagged on the AireOS controller along with DHCP options on the internal DHCP Options are 241, 43 and 103.

I don't see any helper address on the user access switches.  I do see helper addresses on the core switches.  so some how users' access switches are getting pointed to the core switches that than point to the DHCP server.

lcollado
Comes here often

Hello everyone, I'm making some progress but, now the wifi client is getting an IP address from the windows DHCP server but the wrong network address.  

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