Hey everyone,

I'd like to thank all you people helping us linux noobs with our problems! Although this is my first post, this forum has really helped me get going on linux! You guys rule!!! Keep it up!!

I have a dual boot winxp/rh9 system and I'd like to get internet connection sharing working on RH9 with another machine that's win98 (winxp/rh9 is gateway). On winxp, the internet sharing works but I can't seem to get it to work on linux. I'm using a cable modem with the internet abled machine /w DHCP.

The LAN is up and running with samba installed and I am able to ping both machines from either machine so I think it's a question of iptables.

I typed these in the the shell as was suggested by some people but my other machine still can't access the net.

iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT
iptables -A POSTROUTING -t nat -s $CLIENT_IP -j MASQUERADE

A few people also mentioned firestarter but when I went on their website, they only had RH8 rpms... Can I install RH8 rpms on RH9?

Thanks!

P.S. Is there anyway to change the scroll speed on the mouse on RH9?


Here's my ifconfig output:

eth0 Link encap:Ethernet HWaddr 00:80:C6:EC:CB:37
inet addr:xx.xx.xx.xx Bcast:24.82.59.255 Mask:255.255.252.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:6343 errors:0 dropped:0 overruns:0 frame:0
TX packets:6555 errors:0 dropped:0 overruns:0 carrier:0
collisions:7 txqueuelen:100
RX bytes:5335328 (5.0 Mb) TX bytes:986120 (963.0 Kb)
Interrupt:5 Base address:0xe000

eth1 Link encap:Ethernet HWaddr 00:20:78:06:58:44
inet addr:192.168.0.1 Bcast:192.168.0.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:478 errors:0 dropped:0 overruns:0 frame:0
TX packets:354 errors:4 dropped:0 overruns:0 carrier:8
collisions:0 txqueuelen:100
RX bytes:47818 (46.6 Kb) TX bytes:34836 (34.0 Kb)
Interrupt:9

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:63277 errors:0 dropped:0 overruns:0 frame:0
TX packets:63277 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:4317042 (4.1 Mb) TX bytes:4317042 (4.1 Mb)

Have you got 192.168.0.1 set as the gateway for the 98 machine (I think you probably use 192.168.0.1 for both xp and linux - am I right?)

On the 98 box can you ping either:
ping www.linuxquestions.org
ping 64.179.4.146

If the answer is no to both then try:
echo 1 > /proc/sys/net/ipv4/ip_forward

If you can ping the ip then check your DNS settings on 98. If that fails can you post the output of iptables -L

Yep, both OS's use 192.168.0.1 and gateway on the other machine is also set to that IP.



Nope, I can't ping either. When I ping www.linuxquestions.org, no output happens and it just stalls until I ctrl+c out.


Here's my iptables -L output


Chain INPUT (policy ACCEPT)
target prot opt source destination
RH-Lokkit-0-50-INPUT all -- anywhere anywhere

Chain FORWARD (policy ACCEPT)
target prot opt source destination
RH-Lokkit-0-50-INPUT all -- anywhere anywhere

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Chain RH-Lokkit-0-50-INPUT (2 references)
target prot opt source destination
ACCEPT udp -- ns2wh.vc.shawcable.net anywhere udp spt:domain dpts:1025:65535
ACCEPT udp -- ns1wh.vc.shawcable.net anywhere udp spt:domain dpts:1025:65535
ACCEPT tcp -- anywhere anywhere tcp dpt:smtp flags:SYN,RST,ACK/SYN
ACCEPT tcp -- anywhere anywhere tcp dpt:http flags:SYN,RST,ACK/SYN
ACCEPT tcp -- anywhere anywhere tcp dpt:ftp flags:SYN,RST,ACK/SYN
ACCEPT tcp -- anywhere anywhere tcp dpt:ssh flags:SYN,RST,ACK/SYN
ACCEPT udp -- anywhere anywhere udp spts:bootps:bootpc dpts:bootps:bootpc
ACCEPT udp -- anywhere anywhere udp spts:bootps:bootpc dpts:bootps:bootpc
ACCEPT all -- anywhere anywhere
REJECT tcp -- anywhere anywhere tcp dpts:0:1023 flags:SYN,RST,ACK/SYN reject-with icmp-port-unreachable
REJECT tcp -- anywhere anywhere tcp dpt:nfs flags:SYN,RST,ACK/SYN reject-with icmp-port-unreachable
REJECT udp -- anywhere anywhere udp dpts:0:1023 reject-with icmp-port-unreachable
REJECT udp -- anywhere anywhere udp dpt:nfs reject-with icmp-port-unreachable
REJECT tcp -- anywhere anywhere tcp dpts:x11:6009 flags:SYN,RST,ACK/SYN reject-with icmp-port-unreachable
REJECT tcp -- anywhere anywhere tcp dpt:xfs flags:SYN,RST,ACK/SYN reject-with icmp-port-unreachable

If you think it's an iptables problem:

When I think I'm dropping packets, and want to see what's being dropped, I do something like:

/sbin/iptables -N logdrop
/sbin/iptables -A logdrop -m limit --limit 5/hour --limit-burst 2 -j LOG --log-prefix "IPTABLES MATCH: "
/sbin/iptables -A logdrop -j DROP

/sbin/iptables -A INPUT -j logdrop
/sbin/iptables -A OUTPUT -j logdrop

When you put the last two chains at the very end of your existing INPUT/OUTPUT chains, it will only log and drop the packets that are passing through everything else. That way, you're only logging the ones that are for some reason not being allowed through from another chain (assuming that you're policy is to drop everything first and then allow second).

Then you can just go into /var/log/messages and look for the output to find out exactly what packets are being dropped and can adjust your iptables accordingly.

Hope that helps!!!

did you enable ip forwarding with the echo command shown by david_ross
if not please do so and if you have then make a backup of your iptables and and then run
iptables -t filter --flush
iptables -t nat --flush
now add just enough back to the tables to route the 2 ips and see what you can do if that works add the restrictions back in one at a time.

How would I go about backing up my iptables?

service iptables save

MArgRes, I tried doing what you did but for some reason, it killed my internet connection on the linux machine.

I flushed the iptables just as jchristman suggested and readded these lines

iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT
iptables -A POSTROUTING -t nat -s $CLIENT_IP -j MASQUERADE
echo 1 > /proc/sys/net/ipv4/ip_forward

Still doesn't work...
Here's the new output of iptables -L

Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Chain RH-Lokkit-0-50-INPUT (0 references)
target prot opt source destination

Chain logdrop (0 references)
target prot opt source destination

cp /etc/sysconfig/iptables ~/iptables.bak

Before doing this I would cat this file to make sure everything is there. The differant lines for *filter , *nat, and *mangle
this is the way they should be seperated too (with the * attached to the table name).

you may also want to backup your host.deny and host.allow files and then remove all entries in them.

I don't have any entries in the hosts.allow and hosts.deny files.

-A FORWARD -d 192.168.0.0 -i eth1 -p tcp -m tcp --dport 80 -m state --state NEW -j ACCEPT

replace the 192.168.0.0 to the ipaddress your are forwarding to
you might need to also change eth1. You need to due this for all ports you wish to forward.
give this a try

with the above iptable command eth0 is the internet line and eth1 is the inside line.
so it says to forward everything i receive to the inside card and to this ipaddress.

that will make you act like a router though

Would that be the gateway ip address?