A persistent network issue is impacting connectivity for workstations in a training lab when connecting...

The fault domain is DHCP forwarding, not RF, client-side addressing, or AP discovery. Cisco explains that when a wireless client associates, it sends a DHCP Discover broadcast, and depending on AP mode, that traffic is either forwarded through the WLC or passed to the next hop. Cisco further states that if no DHCP server exists in the client’s local Layer 2 domain, the router or SVI for the client VLAN must forward DHCP discovery traffic using an IP helper address.

Because the APs are inLocal mode, client traffic is centrally switched through CAPWAP to the WLC, where the client VLAN/SVI path must correctly relay DHCP toward the DHCP server. Cisco’s Catalyst 9800 DHCP configuration guide shows DHCP relay configuration under the client VLAN SVI by entering the IPv4 helper address, and the CLI example usesip helper-address < ip-address > to forward UDP broadcasts such as DHCP requests.

Option C resolves the issue because all clients are affected and none receive a DHCP offer, indicating the DHCP Discover is not reaching the DHCP server or the offer is not returning through the relay path. DHCP option 43 is for AP controller discovery, not client DHCP addressing. Reference topics:DHCP relay, Local mode AP forwarding, Catalyst 9800 client VLANs, and wireless client IP assignment.