EIGRP Unequal Load Balancing

[fabio.marino]

Hi to all, i have a simple question.

In case of unequal load balancing traffic forwarding, in the contest EIGRP, it is allowed to use the command "maximum-path"?

Thanks, Fabio.

[cadet alain]

hi,

Yes of course you can .

Regards.

Alain

[fabio.marino]

Thanks Alain for your time.

Problem is that i have to solve a question, preparing my ccnp exam: i have a topology and i have to indicate which command adopts in order to forward traffic to a destination, using multiple path.

These paths have different cost so i have to use unequal-cost load balancing (EIGRP is the routing protocol).

I can choose between two options:

-traffic-share balanced: share traffic to all paths proportionaly with cost of each path

-maximums-path "-n": select "-n" paths

Based on Cisco documentation, i would have chosen the first one, traffic-share balanced and not maximum-path.

In case of unequal-cost load balancing, using maximum-path "-n", you  wolud use "-n" paths without any consideration about the cost of each path: i think is not correct.

What do you think?

[cadet alain]

Hi Fabio,

-You must have a maximum path >= to number of paths you want to use for Load balancing and the default is 4 but you can go up to 16 now but this command is not specific to unequal cost load balancing.

-traffic-share balanced is used for unequal cost load balancing but it is the default

-you must also use the variance command which is not default and it is mandatory to do unequal cost load balancing

So of the 2 propositions the traffic-share balanced  seems the good answer but you should post the exact question because we are lacking details here.

Regards.

Alain.

[fabio.marino]

Hi alain,

in my previous post you can find the question (indicating subcommands in order to use all path that reach the same destination), however you confirm what i'm thinking.

Finally we can say:

-you can use maximu-path command in a unequal-cost load balancing contest but this have no sense, right?

Thanks.

[cadet alain]

Hi Fabio,

you can use maximu-path command in a unequal-cost load balancing contest but this have no sense, right?

No, It could make sense if the number of paths was greater than the default which is 4 or if we wanted to use only a subset of all the available paths.

Regards.

Alain.