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IS-IS Lab 25 Route Filtering

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Download Lab: VIRL | EVE-NG | GNS3


Image requirements:

Cisco IOSv (vios-adventerprisek9-m.vmdk.SPA.156-2.T)


Introduction:
In IS-IS terminology the way routes get propagated between different types of areas determine what we call the operation, for example, when there is a necessity to redistribute prefix from L2 area into L1 area this would be the route leaking because by default no routes known to L2 area appear in L1 area.
However, all routes of the L1 area automatically get into the L2 area but sometimes not all prefixes needed to be available in the L2 area and some filtration technique should be in place to prevent route propagation. This lab demonstrates how to enable prefix filtering in IS-IS topology. 


Topology: 




Scenario: 
A new loopback 1 interface has been added to the router A2's configuration to simulation additional subnets for both IPv4 and IPv6. These prefixes by default get redistributed to other areas in the topology. Router A1 is L1/L2 node for area A000…

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