pfSense

VXLAN interfaces are created with a VXLANDEV interface when operating in unicast mode resulting in:

vxlan0: cannot initialize interface: can only specify interface with a group address

The interface creation logic does not match other tunnel type interfaces (GRE, GIF) resulting in interfaces being created multiple times and with the wrong number:

Configuring WAN interface...
vtnet0: link state changed to UP
vxlan0: Ethernet address: 58:9c:fc:10:cb:30
vxlan0: link state changed to UP
done.
Configuring VXLAN0 interface...done.
vxlan1: Ethernet address: 58:9c:fc:10:ff:9f
vxlan1: network identifier 12345 already exists in this socket
vxlan1: network identifier 12345 already exists in this socket
Configuring LAN interface...
vtnet1: link state changed to UP
done.
vxlan2: Ethernet address: 58:9c:fc:10:ff:99
vxlan2: link state changed to UP