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Help with IP forwarding

I have a cable modem connection that is just being converted to a
"business-class" connection, which means I get 5 statics IP addresses
and my packets destined to the office are routed directly.

I can't get IP forwarding to forward anything.

The setup is simple: (I've disguising actual IP's in this message as
just "1.1.1.n"):

cableModem  <--->  LinuxBox  <--->  Win95Box
                  .244 .245         .246

The Linux box has two ethernet cards.

I can ping Win95 from Linux, ping and telnet from Win95 to Linux, but
Win95 can't reach beyond Linux, and from outside the cable modem I can't
see past Linux. IE, it's as if IP forwarding isn't forwarding.

eth0 is the cable modem side:

#  configure the IP address, netmask and broadcast address.
sudo /sbin/ifconfig eth0 netmask broadcast
# add a network route to point to it:
sudo /sbin/route add -net device eth0
# Add a default route.                             
sudo /sbin/route add default gw

eth1 is the Win95 lan side:
sudo /sbin/ifconfig eth1 netmask broadcast
sudo arp -s 00:10:4B:1E:A4:1B pub
sudo arp -a
sudo /sbin/route add -host device eth1
sudo /sbin/route add -host device eth1

Note that my local lan isn't a subnet, just one host (Win95) with houst
routes defined for the ethernet card ( and Win95 (

tcpdump on eth1 while Win95 is trying to ping the cable gateway just
shows the following, with no activity on the other side (eth0):

11:01:24.296343 arp who-has tell
11:01:25.796343 arp who-has tell
11:01:26.816343 arp who-has tell

I tried to turn on logging with this command:
/sbin/ipfwadm -A both -W eth1 -i -o

and /var/adm/kern.log shows this:

May  2 11:02:07 timshel kernel: IP acct in eth1 UDP L=70 S=0x00 I=16137 F=0x0000 T=32 
May  2 11:02:07 timshel kernel: IP acct in eth1 UDP L=70 S=0x00 I=16137 F=0x0000 T=32

Any ideas what I'm missing?


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