nanog mailing list archives

Re: clue for the clueless please


From: "Ryan O'Connell" <ryan () complicity co uk>
Date: Tue, 23 Jan 2001 15:36:53 +0000


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 - <ryan () complicity co uk> - 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


Current thread: