Routing loops
- Due to redistribbution.
- Senario
- Two autonomous systems, connected with dual links, redistributing routes.
- Router through R1 learned from R2.
http://hackingcisco.blogspot.com/2011/02/lab-11-ospf-filtering-with-area-range.html
OSPF notes http://bradhedlund.com/notes/ospf/
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