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Load Balancing over 3 * E1

Hello Gents,

Just a question about load balancing over E1 links: I've got two routers linked together by 3 E1 links.

2 * E1 belong to TELCO X which crash a lot and not reliable at all (lot of errors on the links)

1 * E1 belong to TELCO Y which provides good quality of service

---------| <------------- E1 TELCO X ----------------> |----------|

ROUTER 1 | <------------- E1 TELCO X ----------------> | ROUTER 2 |

---------| <------------- E1 TELCO Y ----------------> |----------|

What is the best solution for load balancing traffic in this case:

- Create one single multilink interface which contains all the E1 ?

In this case i'm afraid about real time traffic quality issues because we have errors on E1 from TELCO X.

- Create 3 separates OSPF interconnections ?

in this case the load balancing could be realized via OPSF (equal cost over the 3 links)

Moreover i should be able to realize PBR on both routers to force voice or real time traffic

over the E1 TELCO Y (which has no errors on it).

- Other solutions ??

Thanks in advance for your advices,

Best Regards,


Hall of Fame Super Silver

Re: Load Balancing over 3 * E1

Hello Adrien,

I agree with second solution

I would increase OSPF cost on the E1 link dedicated to VoIP traffic on both ends

Using PBR you can redirect VoIP traffic over the E1 link with increased OSPF cost and all other traffic will go through the other links by normal routing

PBR also has to be configured on both ends

Hope to help