Cant route out after switch 2.4.20 to 2.6.7

I have a dsl connection being serviced by a Slackware router
running 2.6.7., everything works fine at the router. This is a
dual boot machine with 2.4.20 and 2.6.7

On the 2nd ethernet there is another Slackware box (upgraded )
that can communicate with the 2.6.7 router on eth0, but can not
ping or traceroute out via that GWY. DNS is being resolved, but
just timeouts going out. Same result, with/without fwall.

Everything is perfect if I reboot the router with 2.4.20 kernel.

Dont have a clue, since both boxes have been pretty much
updated the same. Suspect a 2.4.20 client box lib or binary can
talk 2.4 but not 2.6 kernel, but all that was added to the
router were modules and bzImage 2.6.7...

DESCRIPTION:
-----------
CPU1: has dsl modem on eth0, local net on eth1
CPU1: dual boot 2.4.20 or 2.6.7

CPU2: has the local lan on eth0
CPU2: 2.4.20

CPU2's route shows the gwy, etc, exactly the same w/CPU1 2.6.7
as w.CPU1 2,4.20, the same applies to route and ifconfig

CPU1 shows the same for both ethers on 2.4.20 or 2.6.7 (route &
ifconfig).

CPU1 can connect to google, etc in either kernel (both build
locally by doing a make oldconfig of the 2.4.20 kernel
..config)

>
> What does a traceroute to an external host (say
> www.google.com) show?
CPU2: traceroute, just *** after listing the IP being traced;
ping returns failed cnt.

>
> Can the gateway machine see the outside world?
Its a static IP server, it can be seen from the outside
and see the outside as well, with both kernels.

>
> On the gateway machine, what does `cat
> /proc/sys/net/ipv4/ip_forward` show?
Thats independent of the kernels, since it is set to 1 by the
boot scripts.
ans: 1

>
> Does the gateway machine have anything set up to actually
> forward traffic from the internal LAN (the Slack 8.1 box) to
> the outside world?

I have ran http:// www.sysdev.org for the last 5 years on it.
The local lan has always been able to route out thru that GWY.

Anyone can help me with any clues where I continue the
investigation? Googleing, showed that someone else had reported
same problem, but no solution, yet...

Thanks in advance,
TonyB

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On Wed, 28 Jul 2004 17:44:10 +0000
Joaco <(E-Mail Removed)> wrote:

> On the 2nd ethernet there is another Slackware box (upgraded )
> that can communicate with the 2.6.7 router on eth0, but can
> not ping or traceroute out via that GWY. DNS is being
> resolved, but just timeouts going out. Same result,
> with/without fwall.

FYI:
NOT COMPILING with the OPTIMIZE_FOR_SIZE enabled in your
..config's "General Setup Section", when using gcc-3.3.4, seems
to solve the problem!

TonyB

--
__ __ _ I N C. http://www.sysdev.org
/ __|\\// __|| \ __ __ / (E-Mail Removed)
\__ \ \/\__ \||)|/ O_)\/ / \/ System Tools / Utilities
|___/ || ___/|_ /\___|\_/ WIntel / Linux Device Drivers