Strange connectivity issue Frontier EVPL

will at will at
Fri Nov 6 17:54:53 UTC 2020

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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