[tulip] network weird?

John Sutton john@scl.co.uk
Wed Sep 4 08:44:00 2002

Hi there

Sorry this is way OT but I'm desperate...

I'm building a cut down system as a rescue system to boot off DiskOnChip
and I've hit a really extraordinary gotcha...

I started from a RH7.1 rescue image but running with a 2.4.18 kernel on a
box with two tulip cards.

I've cut the system right down to try to isolate the problem so I'm doing
name resolution using /etc/hosts only (so host.conf contains only the
single line "order hosts") and /etc/hosts itself contains only the single
line:   localhost

After booting the kernel and bringing up the lo interface:

ping localhost     - works

ifconfig eth0

ping localhost     - works

ifconfig eth0

ping localhost
ping: unknown host localhost    - name resolution has failed!

ifconfig eth0

ping localhost     - works

In summary, I can configure the interface with any IP 192.168.X.Y
and everything is fine *except* with an IP from the .1.0 network!  If I
choose one of these IP's, name resolution fails.  Note that the interface
is actually up and so I *can* ping and but not using
a name - /etc/hosts is completely ignored until I either bring the
interface down or reconfigure it with another IP *not* in the .1.0 network.

I can't really believe what I've just written and would expect any sane
person to just call me a nutter and ignore this post ;-(  But it's true!

I've tried it on 2 different machines with the same result.  And to add
insult to injury, if I boot this *same* kernel but give it a root device
containing a full blown RH 7.1 system, then the problem disappears.

So it appears that I have cut something out and in so doing exposed some
"special significance" of the network?  But where is it?  My
first thought is that it has to be in some library code that I've removed
from the rescue system, so I reverted the rescue system to use the original
/lib and /usr/lib but the problem still persists.

I'm completely baffled!  Any ideas?


John Sutton
SCL Internet
URL http://www.scl.co.uk/
Tel. +44 (0) 1239 711 888