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Split horizon with poison reverse

auos

Hi,

I have below network

R1

R2 (Fa0/1) --- (172.30.22.1/24)

The network connected to interface (Fa0/1) on Router2 was down; therefore R2 triggered partial update about this network as poison to R1.

My question is why R1 is advertised the poison reverse back to R2 about this network, what the benefit for that.

BR,
Auos.

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Comments

blackninja

auos wrote: »

Hi,

I have below network

R1
R2 (Fa0/1) --- (172.30.22.1/24)

The network connected to interface (Fa0/1) on Router2 was down; therefore R2 triggered partial update about this network as poison to R1.

My question is why R1 is advertised the poison reverse back to R2 about this network, what the benefit for that.

BR,
Auos.

When a router receives a route poisoning, it sends an update back to the router from which it received the route poisoning, this is called poison reverse. This is to ensure that all routers on a segment have received the poisoned route information.