Should this route be in the EIGRP topology table?

Unanswered Question

I have a network as follows:


mcb-core

t2/1 directly connected to t2/1 on hbg-core

g9/8 connected thru ethernet net to g7/5 on hbg-core

g9/33 directly connected to f0/1 on mcb-vpn


hbg-core

t2/1 directly connected to t2/1 on mcb-core

g7/5 connected thru ethernet net to g9/8 on mcb-core


mcb-vpn

f0/1 directly connected to g9/33 on mcb-core


mcb-vpn originates route (via static redist) to 10.214.210.0/24.


mcb-core#show ip eigrp top 10.214.210.0/24

IP-EIGRP (AS 1): Topology entry for 10.214.210.0/24

State is Passive, Query origin flag is 1, 1 Successor(s), FD is 25856

Routing Descriptor Blocks:

10.214.206.3 (GigabitEthernet9/33), from 10.214.206.3, Send flag is 0x0

Composite metric is (25856/1), Route is External

Vector metric:

Minimum bandwidth is 100000 Kbit

Total delay is 10 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 1

External data:

Originating router is 10.214.206.130

AS number of route is 0

External protocol is Static, external metric is 0

Administrator tag is 0 (0x00000000)

10.214.208.66 (GigabitEthernet9/8), from 10.214.208.66, Send flag is 0x0

Composite metric is (256768/26112), Route is External

Vector metric:

Minimum bandwidth is 10000 Kbit

Total delay is 30 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 3

External data:

Originating router is 10.214.206.130

AS number of route is 0

External protocol is Static, external metric is 0

Administrator tag is 0 (0x00000000)


hbg-core#show ip eigrp top 10.214.210.0/24

IP-EIGRP (AS 1): Topology entry for 10.214.210.0/24

State is Passive, Query origin flag is 1, 1 Successor(s), FD is 26112

Routing Descriptor Blocks:

10.214.208.0 (TenGigabitEthernet2/1), from 10.214.208.0, Send flag is 0x0

Composite metric is (26112/25856), Route is External

Vector metric:

Minimum bandwidth is 100000 Kbit

Total delay is 20 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 2

External data:

Originating router is 10.214.206.130

AS number of route is 0

External protocol is Static, external metric is 0

Administrator tag is 0 (0x00000000)

10.214.208.65 (GigabitEthernet7/5), from 10.214.208.65, Send flag is 0x0

Composite metric is (256512/25856), Route is External

Vector metric:

Minimum bandwidth is 10000 Kbit

Total delay is 20 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 2

External data:

Originating router is 10.214.206.130

AS number of route is 0

External protocol is Static, external metric is 0

Administrator tag is 0 (0x00000000)


mcb-core obviously shows the successor as the path through mcb-vpn (g9/33). However, do I read this correctly in that the feasible successor is hbg-core through the ethernet link (g9/8)?


The reported distance for that link (26112) is higher than the feasible distance for that subnet (25856) as calculated by mcb-core. This is because that path would take traffic through the Ethernet net to hbg-core, then out the 10gig link back to mcb-core, then on to the mcb-vpn. What puzzles me is why that path is shown in the topology table since the reported distance is larger than the feasible distance, thus not matching the feasibility condition for EIGRP?


Thoughts? Am I interpreting things correctly?


Also note that the the mcb-core and hbg-core are 6509s, the mcb-vpn is a 2651. Oddly enough, show ip eigrp top on the 6509 does not give the distances. You have to do show ip eigrp top x.x.x.x/y to get this. I don't know why.

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I may have figured it out, but am not sure.


"show ip eigrp top" simply lists

P 10.214.210.0/24, 1 successors, FD is 25856

via 10.214.206.3, GigabitEthernet9/33


Is it the case that show ip eigrp top x.x.x.x/y shows all items learned, even those which don't meat the feasibility condition and thus aren't feasible successors? Whereas the simple show ip eigrp top shows only successors and feasible successors?

Konstantin Dunaev Wed, 10/24/2007 - 00:33
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"show ip eigrp top all" shows all links, even those which don't meet the feasibility condition.


"show ip eigrp top" should show only those which meet the feasibility condition.


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