Troubleshooting Stub Routing Issues

Unless you have a software or hardware bug which actually prevents stub router functionality, the most common problems with stub routing are prefix advertisement. As stated previously, stub router will advertise only connected and summary routes by default. This happens regardless of whether or not any other routes, e.g. static routes, are included in the configurednetwork statement on the stub router. Consider the topology illustrated in Figure 5-5:

Fig. 5-5. EIGRP Stub Routing

Referencing Figure 5-5, R2 has some directly connected interfaces in the 10.1.1.0/24, 10.1.2.0/24, and 10.1.3.0/24 as well as some static routes: 192.168.1.0/24, 192.168.2.0/24, and 192.168.3.0/24. The router has been configured as an EIGRP stub router as follows:

Following this configuration, R1 (the hub) shows the following entries in its routing table:

To resolve this, the stub router must be reconfigured to advertise statics as follows:

NOTE: If you omit the connected keyword, then only the static routes will be advertised.

Following this configuration change, the routing table of R1 shows the following: