EIGRP split horizon verification

EIGRP split-horizon vs poison reverse

RIP - poison reverse


Split horizon is a concept that is used by [distance vector](/routing-distance-vector-routing-protocols) [dynamic routing protocols](/routing-dynamic-routing-protocols) as a [routing loop](/loops-in-layers-2-and-3) prevention mechanism.  It simply states:

"Never send routing information back in the direction from which it was received."

So any [routing](/routing) information that was received via a particular interface will never be sent out that same interface.

[EIGRP](/eigrp) and [RIP](/rip) are among the routing protocols that use this mechanism.

## Links

https://networklessons.com/eigrp/troubleshooting-eigrp-route-advertisement
https://networklessons.com/rip/troubleshooting-rip

Split-horizon

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Split-horizon

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