Re: Doubts in RD over load-balancing.

 On Sun, 15 Apr 2012 13:11:00 +0530, CCIE KID wrote:
> Hi all
>
> I have an issue regarding RD.. In one of the customer site, they have
> the
> same prefix distributed to another Customer site. But on the other
> customer
> site, For the same prefix, they use to different RD values. I don't
> understand why they are performing this
>
>
> CE1---------------PE1---------------P--------------------PE2--------------------CE2
>
> CE1 and CE2 are in same customer intranets.. But they use two
> different RD
> values inside a VRF for the same prefix.
>
> In order to achieve load balancing they do or else it is some kind of
> constraint in doin this?
>
> How does LoadBalancing achieved using RD.
>
>
>
> --
> With Warmest Regards,
>
> CCIE KID
> CCIE#29992 (Security)
>

 Hi,

 So lets think what the purpose of RD is. The RD makes IPv4 routes
 unique by prepending a 64 bit distinguisher making it a 96 bit VPNv4
 prefix. If we use same RD on multiple PEs then the prefix will be the
 same. Remember that BGP only advertises best path which means that there
 usually would be no load balancing. If we have unique RD then prefixes
 will be different and load balancing/redundancy can occur. Usually the
 RD will be of the form AS:somenumber or AS:loopback where the loopback
 is unique for every PE.

 Best regards,

 Daniel

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Received on Sun Apr 15 2012 - 10:08:22 ART