EIGRP directly connected networks question ?

dtushing123 · ‎10-10-2006

From the output of a show eigrp topo how can I tell which networks are directly connected ?

Here is an example, it does not appear that directly connected networks means choosing "via connected" and I am confused.

P 173.17.3.128/25, 2 successors, FD is 30721, serno 9

via 173.17.10.2 (30721/28160), FastEthernet0/1

via 173.17.3.2 (30721/28160), FastEthernet0/3

P 192.168.0.0/24, 1 successors, FD is 156160, serno 16

via 173.17.0.2 (156160/120256), Fa0/0

via 173.17.10.2 (158720/156160), Fa0/1

P 173.17.10.0/24, 1 successors, FD is 20514560, serno 15

via Connected, Fa0/1

P 173.17.0.0/30, 1 successors, FD is 20514560, serno 15

via 182.16.1.1 (201514560/20512000), Fa0/2

via 173.17.10.2 (201518120/204514560), Fa0/1

P 173.17.1.0/24, 1 successors, FD is 30721, serno 8

via 173.17.10.2 (30721/28160), Fa0/1

via 173.17.3.2 (33280/30721), Fa0/3

P 173.17.3.0/24, 1 sucessors, FD is 28160, serno 3

via Connected, Fa0/3

I take this example from another forum where another person posed the question, here is the answer,

173.17.10.2 is directly connected to 3 networks:

173.17.2.0/24

173.17.3.128/25

192.168.0.0/24

What is the reason for that answer ?

Thanks

jackyoung · ‎10-11-2006

According to below link which describe the "show ip eigrp top" command output :

http://www.cisco.com/en/US/products/sw/iosswrel/ps5187/products_command_reference_chapter09186a008017d02d.html#wp1042641

The "via" indicate where the destination address is learned from. So I believe the "via connected" is the network that is directly connected. I suggest to use "sh ip route" to double confirm it. It shows the connected interface clearly.

Moreover, below link also show the "connected" from "sh ip route" and matched w/ "sh ip eigrp top" output.

http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a00800949ab.shtml

Accroding to the ans. from the post, it said three routes were learned via the 172.17.10.2. You can also say it is a directly connected, but if you say "network", the directly connected network are 173.17.10.0/24 & 172.17.3.0/24.

Hope this helps.