OSPF - Stub network overload

The OSPF overload feature causes the metric to be set to the maximum on flooded OSPF prefixes, which results in the routing device to continue participating in OSPF routing, but prevents it from being used for transit traffic. Traffic destined to immediately attached subnets continues to transit the routing device. This feature introduces following functionalities on the stub router in the OSPF network, when OSPF is overloaded: * Allow route leaking-External prefixes are redistributed during OSPF overload and the prefixes are originated with normal cost. * Advertise stub network with maximum metric-Stub networks are advertised with the maximum metric during OSPF overload. * Advertise intra-area prefix with maximum metric-Intra-area prefixes are advertised with the maximum metric during OSPF overload. * Advertise external prefix with maximum possible metric-OSPF AS external prefixes are redistributed during OSPF overload, and the prefixes are advertised with the maximum cost.