arp problem? Howto fix

[Craig White]

On Thu, 2004-07-22 at 14:18, Gene Heskett wrote:
> Greetings all;
> 
> I apologize if this is a duplicate post, but the first one has not come back 
> in something like 20 minutes.
> 
> Now I have a new problem that seems to be iptables or arp related.
> 
> My network here consists of:
> dsl modem<->router<-eth0(firewall box(gene))<->iptables<->eth1(firewall box(gene))<->netgear switch port1
> netgear switch port 2<->main box(coyote)
> netgear switch port 3<->shop box(shop)
> 
> I've just re-configured the 'main box' with the motherboards LAN connection, an nforce2
> setup using the forcedeth driver.  I was formerly running a D-Link RTL-8139too
> card in that box.
> 
> I can ping anywhere on the local net, or ssh into all of it, but cannot even ping
> the router from gene, but I can ping gene from coyote or vice-versa  in
> sub-millisecond timeings..
> 
> >From shop, I can ping the world, from gene I can ping the world, but I cannot
> seem to get thru iptables from coyote, my main box.  All ip addresses are as 
> they were before the card switch.
> 
> Nothing in the network configuration was changed here on gene, which is where
> I'm posting this from.   The only thing changed on coyote is the bogus MAC address
> of the nforce network port since its not hard coded into the chips, but is a bios entry.
> 
> iptables hasn't changed here, but everything has been either power cycled or
> restarted except this box itself, which has a 72 day uptime ATM.  I see no reason
> to do it since the shop box goes thru the same NAT and MASQUERADE in iptables
> as coyote should be using.  In fact, the shop box is not being named in a
> PORTFORWARD rule but is getting thru anyway.
----
don't know if you've solved this and not entirely sure which FC we are
talking about but I would check for the wrong module being assigned to
the switched NIC in the following places...
/etc/modules.conf
/etc/modprobe.conf
/etc/sysconfig/network-scripts/ifcfg-ethX

I would remove the 'old' module ... rmmod rtl8139too or whatever it was
and insmod the new module if known or simply run kudzu and then restart
network service.

Craig