Subject: Re: Traceroute difficulties
To: NetBSD-Users <>
From: Matthew Fincham <>
List: netbsd-users
Date: 01/09/2003 12:30:58
> On Thu, Jan 09, 2003 at 10:19:55AM +0200, Matthew Fincham wrote:
> > I have a Windows system which is able to do the traceroute - but maybe
it is
> > using ICMP??
> Yes, Windows tracert uses ICMP, and as far as I know, there's no way to
> get it to use UDP.
> > What I am trying to solve is actually a bit more than just getting
> > traceroute to work. I am trying to use sendmail/mail to send mail to a
> > server. The mail's are not getting through though. A look at the mailq
> > indicates it is because there was no route to the host. And yet I can
> > the host. So I though if I can sovle the traceroute problem, I can solve
> > mail problem. Another clue is that I can successfully send mail to my
> > "local" mail server.
> Hmm... if you can ping it, there must be a route to it... the only thing
> I can think of is that the other end is sending back ICMP destination
> unreachable when you try to connect to port 25. However, that doesn't
> make sense if it's a mail server... What happens if you try to
>  telnet mailserver 25
> ?

A telnet to the mailer fails (no route to host) - but while a ping is
successfully running (very confusing).

> And I guess it's only one mail server you're having troubles with? You
> don't have any trouble connecting to other servers?

It seems like it is all "external" (I'm not sure what that means) servers
which fail. I created a Yahoo mail account and tried to send mail to it,
from both my NetBSD (using mail) and Windows (using Outlook Express) and the
NetBSD version failed with a "no route to host" error. Yet these two systems
are on the same network. So I think it is some setting on the NetBSD
machine. Maybe a hosts issue??