queer dns access problem

[Stephen Carville]

On 12/15/07, Bill Tangren <bjt at usno.navy.mil> wrote:
>
> > On Dec 13, 2007 8:02 AM, Bill Tangren <bjt at usno.navy.mil> wrote:
> >
> >> >
> >> > OK. Is the /8 netmask a cut and paste error too?
> >>
> >> No, it is correct.
> >>
> >> >
> >> > Your trouble could be a routing issue: 10.1.5.58/8 and 10.1.1.46/8 are
> >> > on the same subnet as far as the network layer is concerned so there
> >> is
> >> > no reason to go to the default route.  Thats why I asked for a
> >> > traceroute too -- or mtr if you have it installed and it will work.
> >> >
> >> > # mtr -rnc 10 DNS.SERVER.IP.ADDRESS
> >> >
> >> > What netmask is the firewall using for the interface?
> >>
> >>
> >> When the network guy comes in this afternoon, I'll ask. This still
> >> doesn't
> >> explain why it works for one machine, but not the other, when both are
> >> set
> >> the same.
> >
> > I am assuming you've done the usual stuff
> >
> > double checked /etc/resolv.conf
> >
> > checked /etc/nsswitch.conf
>
>
> Did these two.
>
> >
> > Pinged the default gateway.
> >
>
> Ping is shut off on the gateway. I'll ask the firewall guy to turn it on
> long enough to test this.
>
> > Checked the network cabling back to the switch.
>
> Yes, other computers work just fine with this cabling.
>
> >
> > Checked the patch cable.
> >
>
> Patch cable? What is that?

The cable for the RJ45 on the computer ethernet card to the RJ45 on
the wall.  10/100 Mbps requires 2 pair and GigaBit over copper
requires all four.

> > ifconfig to make sure the interface is actually up.
> >
>
> yep.
>
> > ethtool to check that speed and duplex are as expected.
> >
>
> Didn't think to do this. Will try it on Monday.
>
> > Can't think of anything else offhand.
> >
>
> Thanks for the help.

Well, you've pretty much exhausted the "easy" stuff that would be
under a sysadmin's control.  If I think of anything else I'll pass it
aloing.

-- 
Stephen Carville