Need to Understand more on IN/OUT concepts while redistributing


I am bit of confused about IN/OUT concept in Eigrp. If a route is set as OUT how it will perform is it applying to the other AS neighbor or is it applying to its same AS neighbors??

Can you clearify more on this in context with OSPF & Bgp as well.

With regards

Hello Pratesh

The distribute-list in and distribute-list out commands are used to filter networks when they are advertised using dynamic routing protocols. This command is specific to BGP, RIP, IGRP and EIGRP.

When using the distribute-list in command, it filters networks that are received in updates from other routers. So any updates sent to the router with this command (whether the source of the updates is routers in the same AS or a different AS) go through the filter defined in the distribute list.

The distribute-list out command suppresses networks from being advertised to other routers (in the same or different AS) in updates that are sent.

So to review, distribute-list in filters routes on incoming routing updates and distribute-list out stops specific local routes from being shared with other routers.

More information about these commands can be found at the following Cisco documentation: distribute-list in and distribute-list out

OSPF does not use this command, but filtering can be achieved using several methods. These can be further examined in Rene’s lesson called OSPF Distribute-List Filtering.

I hope this has been helpful!


HI, many thanks for the clarification it was easy to understand with your simplified explanation.

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