no of route entries in eigrp table

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Sep 2nd, 2008
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Eigrp will have "Six" entries in routing table for same destination,

Default is "four",

set to "one" to disable load balancing,

if that is the case, why load balacing needs to be disabled,

its good in case of link failure when the primary route fails.

Pls let me know the same.

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satish_zanjurne Tue, 09/02/2008 - 22:14
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This depends on Equal Cost or Unequal Cost Load Balancing.

Equal Cost Load Balancing : Be default 4 equal cost routes will be present in the routing table. Maximum 6 .

Unequal Cost Load Balancing : Here "variance" factor comes in picture.

If variance = 1 then unequal cost load balancing is disabled.

But here still equal cost laod balancing is happening.

HTH..rate if useful..

saravanababu22 Tue, 09/02/2008 - 22:30
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thanks for the same, need one more info...

if we are using unequal cost and variance is one, then as u told, LB is disabled.

while the case of equal cost, what would happen. moreover what will happed if variance is not configured, any default value is considered.

satish_zanjurne Wed, 09/03/2008 - 01:19
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By default variance is 1. It means unequal cost load balancing is disabled & equal cost load balancing is in effect.

If you want to use unequal cost load balancing then increae the value of variance factor.

Let me know for more queries..

HTH..rate if helpful..

saravanababu22 Wed, 09/03/2008 - 01:53
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Lets go for equal cost case.

if there are more than one route with equal path for a single destination, in this case, what will be number of entries routing table.

how many entries will be there in "Successor" & "Feasible Successor".

Is it like more than one route successor.

francisco_1 Wed, 09/03/2008 - 02:04
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The route successor is the active route in the routing table "show ip route". Feasible Successor is a backup route you will find in the eigrp topology table "sh ip eigrp topology". The Feasible successor route will not appear in your routing table since it's used as a backup, only exist in the topology table. If you have multiple route to the same destination with the same metric, then EIGRP will use both routes as successor then you will have 2 active routes in the routing table to load balance. likewise if the same process if you have up to 6 routes with the same metric.

Is that clear?


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