black listing of web traffic

Jon Lewis jlewis at
Tue Feb 9 19:54:49 UTC 2010

On Tue, 9 Feb 2010, Andrey Gordon wrote:

> I have a problem that I can't seem to find a solution to yet. My student
> network is being NATted out and anyone who's on that network had troubles
> accessing random websites.
> For example, going to or would work great,
> but would either not load or take forever to open up.
> I've had that problem last week and thought I tracked it down to the NAT ip
> being black listed with one of the span black lists. Even though that IP is
> not used for mail out, that somehow seemed to affect it. Changing it to a
> different one seemed to solve the problem and I got that original address of
> the list in the mean time. Changed it back and everything was well, until
> today.
> Same symptoms, but now I don't see us listed anywhere.
> The best description of the symptoms seems to be that that IP is rate
> limited or something.

Other than the Spamhaus DROP list, I've never heard of blacklisting being 
applied to IP routing.  Were some of your IPs somehow on their DROP list?

  Jon Lewis                   |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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