setting up ip_masqueraiding and firewall on a old linux box
 

HI all,

can someone tell me what i am doin wrong with this setup::::::::::
COM A: 233Mhz PII, 290MB RAM running redhat 8, two NIC's both recognised and apparently working fine.

COM B: AMD Athlon XP2000 1Gb RAM running redhat 8, one NIC (working fine with DHCP)
I configure eth0 on COM A with my cable modem using DHCP (fine). I then setup eth1 as (and I quote) inet addr: 192.168.0.1 Bcast: 192.168.0.255
Mask: 255.255.255.0........... On COM B I configure eth0 as inet addr: 192.168.0.2 (and so on). am i missing something?? i cannot ping COM A from COM B and vice versa the line is dead Wots going on (gggrrrrr) can anyone help this flailing scotsman>>>>>>>>>
Big Cheers in advance

Fokrite

are both interfaces loaded.. i.e. are they listed when you run /sbin/ifconfig? have you got a crossover cable there and not a patch cable?

Hi Chris,

They both show up on the ifconfig command although a couple of times when I was trying to configure them, eth1 was showing errors with TX packets ? though I did configure them so there was no errors and still no joy????...I was wondering if maybe there were files I had to manually update ?
I have tried changing the 10BaseT cable around but that made no difference. Is there something blatant I am missing???

Thanks, well in advance

Not sure what you are asking, but if the the title is the question then machine doing forwarding needs this - in a nutshell:

Change the line net.ipv4.ip_forwarding /etc/sysctl.conf to =1, then restart.
(Or you can just echo 1 > /proc/sys/net/Ipv4/ip_forward and no reboot ;)

This command to make the appropriate entry in iptables.
/sbin/iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE

Be sure to update the GATEWAY= eth1 line in ifcfg-eth0 where eth1 is the route out to net.

Now any non-local traffic will wind up going out eth1 as its the default gateway for eth0.

keep warm.

Thanks mate I will try this out :)