Access Points are not getting IP address from the DHCP server

Summary

Question

Why the Access Points are not getting IP address from external DHCP server?

Customer Environment

Initially, ZD used to provide the IP address for all the Access points and clients. Recently they have deployed an external DHCP server(eg:- Superclick network's SIMS) which could provide the IP address across multiple subnets.

Troubleshooting Steps

* Initially, Access Points were able to obtain the IP address from the DHCP server and joined the ZoneDirector(ZD) but whenever we reboot any Access Point, it never joined the ZD and stays disconnected.

* Access Point can connect back to ZD only if we enable the DHCP server option across the ZD. This AP doesn't even pull out the new DHCP IP address even after performing hard reset.

* All the AP and ZD's traffic is flowing across the untagged vlan 32.

* We took a look at the DHCP server logs, we found that this AP was sending the DHCP discover packet and server is giving DHCP offer packet to the AP. However, we didn't see any DHCP ACK packet received from the AP to the DHCP server.

* Finally, we connected a laptop to the switch port with the same untagged vlan 32 configuration to see if it was able to receive the IP address from the DHCP server and it never did.

* From this test, we confirmed that this is something to do with the DHCP Server configuration.

Resolution

Once after configuring the DHCP Server properly to assign IP address to separate untagged subnet(vlan), Access Points started obtaining IP address from DHCP Server and everything worked fine.

Article Number:
000001955

Updated:
April 08, 2021 12:03 AM (over 3 years ago)

Tags:
Configuration, System Network Management, Troubleshooting, ZoneDirector, ZoneFlex Indoor, ZoneFlex Outdoor

Votes:
15

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