Open Letter to D-Link about their NTP vandalism

Valdis.Kletnieks at vt.edu Valdis.Kletnieks at vt.edu
Mon Apr 10 04:05:17 UTC 2006


On Sat, 08 Apr 2006 11:17:20 CDT, Nicholas Suan said:
> It would be nice if it were that simple. However there are an annoyingly
> large amount of poorly-written clients whose polling ratios do not
> decrease after they get no response from the server. There have even
> been some clients whose polling rate *increases* after they get no
> response.

One particular piece of crapware of the tucows archive variety would retry
once per second if it hadn't heard a response - but a ICMP Port Unreachable
would trigger an *immediate* query, so it would basically re-query at whatever
the RTT for the path was.

Said software was why instead of leaving NTP disabled on the before-mentioned
box, and hoping that at least *some* people would clue in from the ICMP reply,
I had to basically firewall and drop the packets entirely.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 226 bytes
Desc: not available
URL: <http://mailman.nanog.org/pipermail/nanog/attachments/20060410/f258549c/attachment.sig>


More information about the NANOG mailing list