Equal Cost Load Balancing on OSPF (OR) Equal Cost Load Sharing on OSPF (or) Equal Cost Multipath Load Balancing on OSPF

[r20039r20039]

Hi Friends

Which term is correct ?

Equal Cost Load Balancing on OSPF  OR

Equal Cost Load Sharing on OSPF or

Equal Cost Multipath Load Balancing on OSPF 

I want to achieve Equal Cost Load Balancing (What is this actually?) over OSPF which will also support Failover  between R2 and R3. 

I am confused about Equal Cost Multipath (ECMP) and ECBL (Equal Cost Load Balancing) . 

Do they both support Failover? 

I have tested 

                                                           OSPF

    PC1-----------Router 1 ----------------------------------------Router2-------------PC2

                                     -----------------------------------------

In the above scene, If I have tested that any file sent from PC1 to PC to uses both the parallel Links at the same time and severing any of the links still sees the attached link sending data to PC2 . What is this called?

 What if I have a topology like the following? Would that be called as ECBL or ECMP ? Very confused.

[dukenuk96]

Hi

all three terms mean the same feature when we talk about OSPF, in documentaion it is called ECMP. Failover is supported, even more - active-active is on by default, number of paths with the same cost allowed by default and configurable depends on your exact hardware and software.

In your first diagram - between R1 and R2 - two different L3 links or port-channel configured? Actually one pair of IP-IP should use only one path, because by default load-balancing is done by hashing algorithm.

In your second diagram neither load-balancing/failover/multipath would be used, becuase there is no redundant connections between any rotuers.