[2.0b4] cannot create a dynamic range when an observed IP address exists

[Blake Rouse]

I created an IP range on for a subnet that is on a VLAN that MAAS is providing DHCP.

192.168.122.100 - 192.168.122.200

I then DHCP a client which got the address 192.168.122.100

I then deleted the IP range and tried to create the exact same range:

ubuntu@maas:~$ maas admin ipranges create type=dynamic start_ip=192.168.122.100 end_ip=192.168.122.200
{"start_ip": ["No dynamic range can be created at requested start IP."], "type": ["No dynamic range can be created at requested start IP."]}

The only IP that exists in that subnet is 192.168.122.100 which is Observed, as it was the client that initial DHCP'd.