OSPF

OSPF
When redistributing into OSPF, it is not required to set a metric. If a metric is not stated, the
default will be 20. It is a good idea to set the metric so all of the redistributed routes do not have
the same metric.
Because OSPF is a classless routing protocol, it accepts routes that are not of classful boundaries.
In order for OSPF to accomplish this, you need to append the keyword subnets to the end
of the redistribution line. The subnets keyword allows for classless routes to be redistributed
into OSPF. Without the subnets keyword, OSPF will accept only classful routes and will reject
classless routes. Refer to Figure 10.9.