Spilt Horizon - Sub Interface

mattsthe2

Ok im going to ask probably a really stupid question but...

Doesnt sub-interfaces vialate the Spilt-Horizon rule?

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Comments

dtlokee

What do you mean by "validate"?

Since each sub interface is treated as a seperate interface for split horizion, updates learned on one sub-interface are able to be sent out another sub-interface. The fact that they are both tied to the same physical interface doesn't affect split horizion in this case.

mattsthe2

dtlokee wrote:

What do you mean by "validate"?

Since each sub interface is treated as a seperate interface for split horizion, updates learned on one sub-interface are able to be sent out another sub-interface. The fact that they are both tied to the same physical interface doesn't affect split horizion in this case.

Sorry i mean violate.

But you did answer my question. It is seen as a seperate interface even though its on the same physical interface.

Thanks,