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Configure ISO Addressing



For a router to support IS-IS, you must configure an ISO network entity title (NET) address on one of the router’s interfaces, preferably the loopback interface (lo0).


To configure ISO addressing, follow these steps:

  1. In configuration mode, go to the following hierarchy level:

  2. Include a NET address for the loopback interface:

  3. Verify and commit the configuration:

Sample Output


The sample output shows that the loopback (lo0) interface is configured with the NET address 49.0004.1000.0000.0001.00. The loopback interface (lo0) becomes a point of connection from the router to the IS-IS network. Every router in an IS-IS network must have at least one ISO NET address that identifies a point of connection to the IS-IS network. The NET address is generally configured on the loopback (lo0) interface. Routers that participate in multiple areas can have multiple NET addresses.

All the routers in the network share a Level 2 database containing identical information. A common Level 2 database occurs in this case because all adjacencies are Level 2, and all routers are within the same IS-IS area (49.0004). Level 2 LSP flooding reaches all routers in the network due to the presence of a single level. For more information on determining the NET address, see the Junos Routing Protocols Configuration Guide.