Redistribution seed metrics

Redistributed routes are treated differently depending on which routing protocol they are being redistributed into. On IOS, each routing protocol has its own seed metric which is assigned by default to redistributed routes when no metric is configured manually. Below is a table listing the default behavior when no metric is defined with the metric argument on the redistribute command.

Source Into
RIP EIGRP OSPF ISIS BGP (MED)
Connected 1 Int metric 20 (E2) 0 0
Static 1 Int metric 20 (E2) 0 0
RIP Infinite 20 (E2) 0 IGP metric
EIGRP Infinite 20 (E2) 0 IGP metric
OSPF Infinite Infinite 0 IGP metric
ISIS Infinite Infinite 20 (E2) IGP metric
BGP Infinite Infinite 1 (E2) 0

As illustrated in the table, routes being distributed from another routing protocol into RIP or EIGRP must have a configured metric to be eligible for placement in the RIP database or EIGRP topology. Also interesting to note is that BGP will automatically assigned the IGP-learned metric of a redistributed route to the route's MED in the BGP table.

About the Author

Jeremy Stretch is a freelance networking consultant, instructor, and the maintainer of PacketLife.net. He currently lives in Fairfax, VA on the edge of the Washington, DC metro area. Although primarily an R&S guy, he likes to get into everything, and runs a free Cisco lab out of his basement for fun. You can contact him by email or follow him on Twitter.

Comments

awesomeness, pure awesomeness

Hey - is it possible to find this info on the cisco website as I've spend 2 days without a luck ? Did you find any refrence for seed metric values for Juniper ?

Patryk, check page 384-386 in the book Building Scalable Cisco Internetworks (BSCI) Third Edition. A book used for CCNP learning.

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