OSPF Edge Mode
OSPF Edge Mode is a subset of OSPF available on platforms with an Advanced Edge license.
There are two restrictions on OSPF Edge Mode:
At most, four Active OSPF VLAN interfaces are permitted. There is no restriction on the number of Passive interfaces.
The OSPF Priority on VLANs is 0, and is not configurable. This prevents the system from acting as a DR or BDR.