On Sun, Feb 01, 1998 at 01:46:35PM -0700, Marc Slemko wrote:
> > 13:44:04.878280 mailhost.orion.fi.34036 > kyyhky.jmp.fi.smtp: P 138:1598(1460) ack 373 win 8760 (DF)
> > 13:44:04.878446 muikku.jmp.fi > mailhost.orion.fi: icmp: kyyhky.jmp.fi unreachable - need to frag (DF)
> 
> The problem isn't the system, but rather that some dumb admin has decided
> to filter all ICMP.

They allowed ICMP through their firewall and now the mail message got
through.

I still don't understand why they try to send packets of 1460 bytes with DF
set..

BTW, what's the basic idea of DF, anyway?  The fragmented packets will be
reassembled at the receiving end, so why not allow fragmenting and let the
routers do what they have to? :-)  (A stupid question probably, but it had
to be asked.. ;)  Sure, it may affect performance with high packet losses,
but..

  -jm