Eigrp variance issue

kpjungle

Hi,

Im having a problem with EIGRPs variance command.

I have a 3 router setup, meaning I have redundant paths. From one of the routers (R3), I would like to use the variance router command to load balance (unequal).

I have configured the R3 router with the variance command, and can only see this:

(abbreviated)
R3#sh ip eigrp topology
P 10.1.2.0/30, 1 successors, FD is 40640000
         via 10.1.203.2 (40640000/128256), Serial0/1

So I have a successor, and the following confirms, I dont have a feasible successor because the advertised distance of the other router is equal to the current FD (must be less), but there IS a different route to the destination:

R3#sh ip eigrp topology 10.1.2.0 255.255.255.252
IP-EIGRP topology entry for 10.1.2.0/30
  State is Passive, Query origin flag is 1, 1 Successor(s), FD is 40640000
  Routing Descriptor Blocks:
  10.1.203.2 (Serial0/1), from 10.1.203.2, Send flag is 0x0
      Composite metric is (40640000/128256), Route is Internal
      Vector metric:
        Minimum bandwidth is 64 Kbit
        Total delay is 25000 microseconds
        Reliability is 255/255
        Load is 1/255
        Minimum MTU is 1500
        Hop count is 1
  10.1.103.1 (Serial0/0), from 10.1.103.1, Send flag is 0x0
      Composite metric is (41152000/40640000), Route is Internal
      Vector metric:
        Minimum bandwidth is 64 Kbit
        Total delay is 45000 microseconds
        Reliability is 255/255
        Load is 1/255
        Minimum MTU is 1500
        Hop count is 2

Also, it is not reflected in my routing table:

(abbreviated)
D       10.1.2.0/30 [90/40640000] via 10.1.203.2, 00:38:41, Serial0/1

But shouldnt the "variance 2" command rectify this? shouldnt i see two routes to the same destination in my routing table? and would it appear in my standard topology table as well?

Either way, i tried debugging packets on R3 while pinging the destination (10.1.2.1), but to no good, it uses the same path no matter what.

singh8281

Look closely to the AD from the 10.1.103.1, it wouldn’t qualify for variance because it has an AD equal to the FD of the successor. In order for that router to become part of the load balance it must have an AD less than the FD of the current successor.

kpjungle

singh8281 wrote:

Look closely to the AD from the 10.1.103.1, it wouldn’t qualify for variance because it has an AD equal to the FD of the successor. In order for that router to become part of the load balance it must have an AD less than the FD of the current successor.

Ahh, got it. It must be a feasible successor in order to be considered for the variance to begin with.

Thanks!