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Re: [vox-tech] I'm also having ntp problems :-(
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Re: [vox-tech] I'm also having ntp problems :-(

On Wed, Apr 24, 2002 at 11:21:56PM -0700, Ryan wrote:
> On Wednesday 24 April 2002 11:11 pm, msimons@moria.simons-clan.com wrote:
> > On Wed, Apr 24, 2002 at 11:04:01PM -0700, Ryan wrote:
> > > The following seems to be happening...
> > >
> > > connections to a udp server on nat work fine both ways.
> > >
> > > connections to a udp server on bob only work for sending data to bob.
> > >
> > > in tcpdump, I see nat telling bob that the udp port is unreachable, yet
> > > bob has no firewall.
> > >
> > > Very odd.....
> >
> >   Can you paste a 10 line tcpdump log showing this event?

my bad, I kinda expect a verbose tcpdump...
  tcpdump -tteni eth0
-tt switches to a better time format,
-e shows ethernet mac address info
-n doesn't do name/server lookups so it's harder to hide errors.
-i eth0 : you know this

  I would like a trace of the same even from both hosts bob and nat...
since tcpdump's view of events is sometimes faked out by firewall
rules on the machine running the dump (things it sees don't really 
happen on the wire).

> 23:18:56.151057 bob.ntp > nat.ntp:  [udp sum ok] v4 client strat 0 poll 4 prec -6 dist 1.000000 disp 1.000000 ref (unspec)@0.000000000 orig 0.000000000 rec -0.000000000 xmt -1066262965.417984008 (DF) (ttl 64, id 0, len 76)
> 23:18:56.151341 nat > bob: icmp: nat udp port ntp unreachable for bob.ntp > nat.ntp:  v4 client strat 0 poll 4 prec -6 dist 1.000000 disp 1.000000 ref (unspec)@0.000000000 [|ntp] (DF) (ttl 64, id 0, len 76) [tos 0xc0]  (ttl 255, id 20476, len 104)
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