From: Matt Sherman (matt.sherman2@gmail.com)
Date: Sat Dec 22 2007 - 17:16:09 ART
Hello,
I'm having some problems determining why a certain route is put into the
routing table when it has a higher cost than one being received from another
router.
Here's the scenario. Router R4 is receiving redistributed EIGRP routes from
R2 and R3. If I advertise them equally it works as planned.
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R4#sh ip route 145.0.0.0
Routing entry for 145.0.0.0/22, 1 known subnets
O E2 145.0.0.0 [110/20] via 172.16.2.3, 00:01:36, Serial1/0
[110/20] via 172.16.2.2, 00:01:36, Serial1/0
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However if I set redistribution on R2 with a metric-type of 1, R2's route
becomes more preferred even though its metric is higher than R3's.
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R4#sh ip route 145.0.0.0
Routing entry for 145.0.0.0/22, 1 known subnets
O E1 145.0.0.0 [110/84] via 172.16.2.2, 00:00:30, Serial1/0
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I can see it being deleted from the route table
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*Mar 1 04:28:52.078: RT: ospf's 145.0.0.0/22 (via 172.16.2.2) metric
changed from distance/metric [110/20] to [110/84]
*Mar 1 04:28:52.082: RT: del 145.0.0.0/22 via 172.16.2.3, ospf metric
[110/20]
*Mar 1 04:28:52.086: RT: NET-RED 145.0.0.0/22
*Mar 1 04:28:52.086: RT: NET-RED 145.0.0.0/22
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If I manually specify the same metric of 84 on R2, the router goes back to
preferring R3's route with a metric of 20.
redistribute eigrp 200 metric 84 subnets
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*Mar 1 04:32:15.950: RT: del 145.0.0.0/22 via 172.16.2.2, ospf metric
[110/84]
*Mar 1 04:32:15.954: RT: delete subnet route to 145.0.0.0/22
*Mar 1 04:32:15.958: RT: NET-RED 145.0.0.0/22
*Mar 1 04:32:15.958: RT: delete network route to 145.0.0.0
*Mar 1 04:32:15.962: RT: NET-RED 145.0.0.0/16
*Mar 1 04:32:15.966: RT: SET_LAST_RDB for 145.0.0.0/22
NEW rdb: via 172.16.2.3
*Mar 1 04:32:15.970: RT: add 145.0.0.0/22 via 172.16.2.3, ospf metric
[110/20]
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