Which route takes priority?

[dan_track]

Hi,

I've read that a static route will take priority over a route learned via a routing protocol becuase the static route has a lower AD compared to the routing protocols. I'm a little unsure as to what this means, let's say we have the following routesin the routing table

Routing Protocol      Network/Subnet      Next Logical Hop      Metric
RIP                         10.10.10.8/30         140.100.3.2              1 hop
RIP                         10.10.10.12/30       140.100.3.2              1 hop

If I then create a static route like

ip route 10.0.0.0 255.0.0.0 140.100.3.1

Would the above RIP routes then disappear from the routing table? So then all you would have in the routing table is:

Routing Protocol      Network/Subnet      Next Logical Hop      Metric
STATIC                   10.0.0.0/8              140.100.3.1               1

Is that right?

Where does the part that I have read that specific routes are favoured more than generic routes, how does that play a part given that the RIP routes are more specific that the static route?

Thanks in advance for any help.

Dan

[Federico Coto Fajardo]

Hi Dan,

Always the most specific the route, it will take precedence (does not matter if it learned it via static or dynamic protocols)

Only in the case when a route has exactly the same prefix length, for example (10.0.0.0/24 via RIP and 10.0.0.0/24 via STATIC), in this case the static will take precedence due to its lower AD.

You can manipulate the AD, so that you can have the routing protocol getting chose over a static route (for same length prefixes routes).

Federico.