3.27 Configure And Verify Ospf Path Preference

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Key Topic

The choice ofthe best route for a given subnet, and calculated by a particular router, can besummarized as follows:

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Analyze the LSDB to find all possible routes to reach the subnet.

For each possible route, add the OSPF interface cost for all outgoing interfaces in that route.

Pick the route with the lowest total cost

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To add cost go to each router interface and add up.

show ip ospf interface

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.to fix:

auto-cost reference-bandwidth

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intra-area is always preferred over inter-area even if cost is higher

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