Route Selection
The router will use all the available sources of reachability information to construct the most accurate and efficient routing table possible, based on the available information. Each information source is assigned an administrative distance, which is used to determine a route's integrity. Table 10.2 lists the IOS's default administrative distance values for its supported IP routing protocols.
| Protocol | Distance |
|---|---|
| Connected interface | 0 |
| Static route | 1 |
| EIGRP summary route | 5 |
| BGP (external) | 20 |
| EIGRP (internal) | 90 |
| IGRP | 100 |
| OSPF | 110 |
| RIP | 120 |
| EIGRP (external) | 170 |
| BGP (internal) | 200 |
| Unknown | 255 |
The lower the administrative distance value, the more trusted the route. So, you can see in situations where multiple routing ...
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