Symptom
WLAN is using EoGRE tunnel configured with DHCP Option 82.
The vlan used in the EoGRE tunnel is not up in the WLC as it is not used anywhere in the network.
During client joining, the DHCP packet leaving the WLC does not have option 82 added.
Conditions
WLAN + EoGRE + Option 82 and VLAN/SVI interface down
Workaround
Allow the vlan in WLC uplink trunk to make it up
