Cisco CCNP / BSCI Certification Exam: Five OSPF Details You Must
Know
Preparing for your BSCI exam on your way to the Cisco CCNP
certification, you can quickly get overwhelmed by the details!
Here are five commonly overlooked points you should keep in mind
when it comes to your OSPF studies.
The virtual link command includes the area number of the transit
area, and if authentication is being used on Area 0, the virtual
link command must include the authentication statement. Since
the virtual link is a logical extension of Area 0, it stands to
reason that it has to be configured with the authentication type
and password configured on Area 0.
OSPF requires no seed metric when routes are being redistributed
into an OSPF domain. The default cost for such routes is 20, but
you do need to use the "subnets" option if you want to
redistribute subnets into OSPF.
There are two kinds of external OSPF routes. The default, E2,
reflects the cost of the path from the ASBR to the external
destination. The other option, E1, has a cost reflecting the
entire path from the local router to the external destination.
When configuring stub areas, each router in the area must agree
that the area is stub. For a total stub area, only the ABR needs
to be configured with the "no-summary" option, but all routers
in the area still must agree that the area is stub.
Routers in a stub area will have a default route to use to reach
external destinations; routers in total stub areas will have a
default route to use in order to reach both external and
inter-area networks.
The BSCI exam and CCNP certification require a great deal of
dedication and hard work. Keep studying and paying attention to
the details, and you will get there!