Is there any data on packet duplication?

Mark Tinka mark.tinka at
Tue Jun 23 06:09:48 UTC 2020

On 23/Jun/20 07:52, Saku Ytti wrote:

> S1-S2-S3-S1 is operator L2 metro-ring, which connects customers and
> 2xPE routers. It VLAN backhauls customers to PE.


In 2014, we hit a similar issue, although not in a ring.

Our previous architecture was to interconnect edge routers via
downstream, interconnected aggregation switches to which customers
connected in order to support VRRP.

Since customers do strange things, both edge routers received the same
traffic, which caused pain.

Since then, we don't support VRRP for customers any longer, nor do we
interconnect aggregation switches that map to different edge routers.

Your example scenario describes what we experienced back then.


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