North American Network Operators Group

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Re: clue for the clueless please

  • From: Ryan O'Connell
  • Date: Tue Jan 23 10:36:53 2001

On Tue, Jan 23, 2001 at 01:59:41PM -0000, Peter Galbavy wrote:
> Yes, we intentionally (for some other reason during testing) set the MTU on
> the p2p link to 554 - oops. Will get it switched back... Still wondering
> though - if a normal dial-up has a lower than 1500 MTU, why would they work.

Sounds almost certainly like an MTU problem. Try www.bt.com, if that fails
then it's pretty much definite. Microsoft are a bit silly for setting the
DF bit on outbound packets, firewalls at web hosting facilities that block
all ICMP are even more silly. Why on earth Microsoft, who must know about this
problem, block ICMP on their kit I don't know...

Most if not all dialup has an MTU of 1500.

-- 
Ryan O'Connell - <[email protected]> - http://www.complicity.co.uk

I'm not losing my mind, no I'm not changing my lines,
I'm just learning new things with the passage of time