Strange connectivity issue Frontier EVPL

Jeff Richmond jeff.richmond at
Fri Nov 6 17:39:33 UTC 2020

Jay, I previously ran the engineering org over there, so sent this to my old team to look at, including the best engineer I know in regard to the RADs. Will pass along anything they come back with.


> On Nov 6, 2020, at 8:59 AM, Jay Hennigan <jay at> wrote:
> We have a strange issue that defies logic. We have a NNI at our POP with Frontier serving as an aggregation circuit with different customers on different VLANs. It's working well to several customers.
> Bringing up a new customer shows roughly half of the IP addresses unreachable across the link, as if there's some kind of load-balancing or hashing function that's mis-directing half of the traffic. It's consistent, if an address is reachable it's always reachable. If it's not reachable, it's never reachable. Everything ARPs fine.
> The Frontier circuit is layer 2 so shouldn't care about IP addresses. Frontier tech shows no trouble. They changed the RAD device on-premise. We've triple-checked configurations, torn down and rebuilt subinterface, etc. with no joy.
> Any suggestions?
> -- 
> Jay Hennigan - jay at
> Network Engineering - CCIE #7880
> 503 897-8550 - WB6RDV

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