Strange connectivity issue Frontier EVPL

Mike Lyon mike.lyon at
Fri Nov 6 18:14:58 UTC 2020

What hardware is on each side?

> On Nov 6, 2020, at 10:08, will at wrote:
> I have similar Frontier NNI's out of One Wilshire, some 1gig some 10.
> While I haven't seen the half-IP-reachable issue you describe I have spent
> days and days chasing performance issues on them. I finally got gig 
> line-rate capable iperf3 boxes at both ends and see distinct differences
> in single-TCP stream performance vs running 3-4 streams, and the difference
> disappears like clockwork at "unbusy hours" (1am-7am) every day.
> After running hundreds of tests and adjusting my buffering and RED on both
> ends of these circuits I just have come to the conclusion that they have
> some LAGs somewhere "in the middle" that get busy during the day, and
> they don't care if I have to run 4 TCP streams to max a 1gig circuit.
> It makes browser-based speedtests look really bad but otherwise the 
> circuits are usable. We're trying to replace the worst ones with 
> wavelength services.
> -Will Orton
>> On Fri, Nov 06, 2020 at 08:59:28AM -0800, Jay Hennigan 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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