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Re: EIGRP Load Balancing [7:101758] posted 08/08/2005
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Hi Alejandro,


that's normal . To load balance with EIGRP between RA and RB  you must have
2 network (to REMOTE_LOC) with equal metric on RA . If all metric are set to
default value then RA and RB will install the network ( REMOTE-LOC) via WAN
link only. In this case the network that RA receives by RB have a major
metric ( count the ethernet metric ) and therefore does'nt install in
Routing Table. According to "Feasible Condition"  RB is not a feasible
successor because his FD is equal to the FD of RA ( if all metric are
default ) and therefore if you type "sh ip eigrp topo" you cannot see RB as
feasible. That is normal.

If you want to balance you have many possibility :


1) Equal-load : configure offset-list on RA serial link to increment of K
constant the metric of network received from Wan .In this way RA will see 2
network with same metric. Command is :


                                                                    router
eigrp 10
                                                                 offset-list
10 in K ser1


     where 10 is ACL number that match the ip network (REMOTE-LOC)

      where K is a number that you found in this way :

                                   K= Mb - Ma

        Ma is the metric to network from RA trough Wan. To take this number
you type sh ip route .............. [90/1024]

       Mb is the metric to the network from RA trough RB. To take this
number you need to force routing towards RB , for ex. you can
passive-interface serial of RA . In this way  the eigrp session with remot
router went down and RA will install network via RB. If you lose connection
to RA don't panic because you can enter in RA in point-to-point from RB or
from remote-router.  When you take this number Mb you must delete
passive-interface ...


2) disequal load balance => configure variance on RA and pay attention to
Feasible condition because to balance with variance is necessary that the RB
is feasible successor...... This way is more complicated , because you need
to change metric on serial link of RA .


3) load balance with MHSRP or GLBPP .




Giuseppe Citerna
ccie#10503

























































""Alejandro Acosta""  ha scritto nel
messaggio news:200508081548.j78Fm2Qu004454@xxxxxxxxxxxxxxxxx
> Hello gurus,
>   I hope you can help me
>   I have the following scenario:
>
> MY-LAN ----- ROUTER A ------ RTR-REMOTE-LOCATION
>                 |
>                 |--- ROUTER B ------ RTR-REMOTE-LOCATION
>
>
> Notes:
> - Router A is the default GW of the LAN
> - All routers are talking EIGRP.
> - RTR-A and RTR-B are in the same IP subnet.
>
> In this moment, all traffic goes from my LAN to the remote location via
> Router
> A. I would like to load balance the traffic between RTR-A and RTR-B (I
mean,
> I don't want to have it as a backup link, I really want to load balance
the
> traffic).
>
> Probably, I would like to set the same metric in RTR-A  to routes learns
> from
> remote locations and from RTR-B. Is it possible?
>
> Thanks,
>
> Alejandro,-




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