I had an issue with the DHCP server configured as specified in the subject. There are the steps to reproduce it:
- Enable DHCP function deny unknown clients
- Add some MAC addresses, enable static ARP and apply mapping changes
Once done, I'm unable to surf or access to pfSense SSH/GUI.
EDIT: I think this is due to the static ARP and MAC addresses list functions: if I don't enter any IP address associated with the MAC address with static ARP enabled, I'm unable to access to pfSense box.