DHCPv4 relay is not working on one VLAN

[iam]

Hi,

I have different VLANs including the main LAN and the WiFi networks. The DHCP server runs on a different server in the main LAN. The opnsense is acts as DHCP relay on all VLANs except the main LAN.

This works inside all VLANs except the guest WiFi. I don't see any related request in the DHCPD log. The guest WiFi subnet is enabled on the DHCP server with a dynamic range. The DHCP relay is enabled for the guest wifi. IPv6 works inside the guest WiFi. But IPv6 is enabled only for the WAN and the guest WiFi.

Has anyone any idea?

Best,
iam

[opns_neuling]

hi!
please post a portion of dhcpd.log files.

[Gauss23]

Wifi hardware manufacturer?

Unifi for example has a feature called DHCP guard. If enabled only the specified DHCP server is allowed for this network. Or maybe you have port isolation enabled for that network?

[iam]

 Hi,

I investigated this issue more. It seems to be an OpenWRT (or hardware?) issue. The bridge of guest wifi and guest VLAN isn't working properly on 2  (same hardware) of 3 devices (different hardware).

Best,
iam