[RndTbl] weird mts latency issue?

Trevor Cordes trevor at tecnopolis.ca
Sun Jan 22 02:55:38 CST 2017

On 2017-01-21 Hartmut W Sager wrote:
> > I don't think I've ever seen DSL behave that strangely...  
> Neither have I.  I suspect your problem is much closer to home than
> MTS DSL.  So, what "innocent, funny things" have you done lately?
> Like, the kind of things that "obviously" can't cause this
> problem.  :)

Solved it, I think.  Yup, you were right.  I think it was a confluence
of things:
1. The box was experiencing massively higher than usual outgoing
2. I use QoS on egress to allow fair bw use to many different
protocols.  I checked and the total rate allowed was set quite low,
because that's what their DSL modem used to allow, but they recently
got a new modem/plan and I ran a test and they now get 10X the *upload*
speed.  So I got to bump up all the QoS speeds.

Now the problem is gone.  I think the QoS stuff might go completely
mental when faced with insane demands.

Looking at the pings where they bunch up, it now is clear that the QoS
was filling up the bucket then allowing a burst through, filling again,

The worst part of it all (and why I noticed the problem) is that DNS
wasn't resolving... timeouts.  I never thought to put DNS UDP 53 in its
own QoS class with dedicated bw, but I'm going to implement this now!

On 2017-01-22 Dan Keizer wrote:
> i have seen that type of issue with mts at a fellow ham place   when
> he was operating the low bands on hf it would cut out his mts
> internet off and on ...
> any BIG antennas around there?

That actually could still be a factor!  We'll see if the problem
recurs.  This office is located in a dense industrial park with all
sorts of weird stuff around.

Would your buddy's DSL "cut off" as in "hang up" (and re-PPPoE connect),
or just drop packets?

Thank to MUUGers once again!

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