an infinite cost can be advertised by an ospf transit router until bgp comes up...
benefit: http://www.cisco.com/en/US/products/ps6599/products_white_paper09186a00800ade18.shtml
- Graceful removal of an OSPF router from
networks (i.e. to upgrade software or to perform maintenance) and
reduction in packet drop
- Reduce black-hole packet dropping when interacting with BGP
this is very exciting...
It can be desirable to have a router in a network that is not a transit router. A "transit router" forwards traffic that is not destined for networks directly connected to the router. A router that only forwards packets destined to its directly connected links is known as a "stub router". In OSPF networks, a router could become a stub router by advertising large metrics for its connected links, so that the cost of a path through this router becomes larger than that of an alternative path. It does not matter what specific metrics are advertised in a stub network that is connected to the router, because data must reach the network via the stub router itself.
and you thought it was safe to go back in the water...
infinity is 16,777,215 in ospf...
that's 2^24 = 16,777,216
this is better than coffee first thing in the morning...
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