EIGRP Stub Routers with Route Leakage

In EIGRP (Enhanced Interior Gateway Routing Protocol), configuring routers as stubs is a powerful feature that offers control over network behavior. This documentation explains the concept of EIGRP stub routers, the types of stub routers, and how to selectively 'leak out' specific routes using route maps.

EIGRP Stub Routers

Types of Stub Routers

EIGRP supports various types of stub routers, each with specific purposes:

• Connected: Advertises any connected interfaces (requires the use of the 'network' command).
• Summary: Advertises summarized networks.
• Receive-Only: Does NOT advertise any networks.
• Redistributed: Advertises routes that have been redistributed INTO EIGRP.
• Static: Advertises static routes.
• Leak Map: Allows specific prefixes to be 'leaked' or advertised from the stub router.

Route Leakage from Stub Routers

One of the advanced features of EIGRP stub routers is the ability to selectively 'leak out' specific routes from the stub. This means that a stub router can be configured to advertise routes that fall outside the typical stub behavior. This is particularly useful when you want to control the propagation of specific routes beyond the stub.

Configuration

To selectively 'leak out' routes from a stub router, use the following configuration command:

• eigrp stub connected leak-map [route-map name]: This command allows you to specify a route map name that defines which routes should be 'leaked' or advertised from the stub.

Verification

To verify and monitor the configuration of EIGRP stub routers with route leakage, use the following commands:

• show ip eigrp neighbors detail: Displays detailed information about EIGRP neighbors, including stub router configurations.
• show ip protocols: Provides information about routing protocols, including EIGRP configuration details.
• debug eigrp packets hello detail: Enables debugging of EIGRP hello packets with detailed information.
• debug eigrp packets terse detail: Enables debugging of EIGRP packets with terse and detailed information.
• eigrp stub: Enters EIGRP stub router configuration mode.
• show eigrp plugins: Displays information about EIGRP plugins and their configurations.

This documentation provides insights into configuring EIGRP stub routers with the option to selectively 'leak out' specific routes, offering greater control and flexibility in managing your network.