internet connection sharing with two red hat computers.

brucedjones · 08-14-2003, 01:12 PM

woah well now i can ping both computers after doing dmesg | grep eth...... but internet connection sharing is still not working

Mathieu · 08-14-2003, 01:54 PM

Now follow the instructions in this post.
http://www.linuxquestions.org/questi...351#post395351

brucedjones · 08-14-2003, 03:43 PM

sorry i dun all that stuff and it still doesnt work

Mathieu · 08-14-2003, 03:52 PM

If you have not restarted your computer since making those modification, you can try:

Code:

service network restart
service iptables restart

If that does not work,
I need to see the output from the two following commands:

Code:

route -n
iptables -L

brucedjones · 08-14-2003, 04:02 PM

[root@localhost bruce]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
172.26.131.0 0.0.0.0 255.255.255.0 U 0 0 0 ippp0
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 172.26.131.160 0.0.0.0 UG 0 0 0 ippp0
[root@localhost bruce]# 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

Does that help

Mathieu · 08-14-2003, 04:16 PM

Yes, it does.
Make sure you do the following and you are root.

Edit the file /etc/sysctl.conf and on the line net.ipv4.ip_forward = 0, change 0 to 1.

Code:

# Controls IP packet forwarding
net.ipv4.ip_forward = 1

In order for the changes to take effect,
at the command line, type: service network restart

Now you need to setup IP forwarding and Masquerading.
First, you need to flush the old rules.
So open a console window and at the command line, type:

Code:

service iptables stop
service iptables save

The following commands will create new rules for your system.

Code:

iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD DROP

iptables -A FORWARD -i ippp0 -o eth0 -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A FORWARD -i eth0 -o ippp0 -j ACCEPT

iptables -t nat -A POSTROUTING -o ippp0 -j MASQUERADE

To save iptables modifications, at the command line, type: service iptables save.
IPtable rules are located in the /etc/sysconfig/iptables file.

Don't forget to start iptables, type: service iptables start

brucedjones · 08-16-2003, 04:55 PM

i set all that up....and its still not working :'(

Mathieu · 08-17-2003, 10:39 AM

I failed ...

and I am running out of ideas.

Make sure the Gateway on your sister's PC is the IP of your PC.

I will assume that you can connect to the internet using your PC.
And that both computers can ping each other.

brucedjones · 08-17-2003, 11:17 AM

gateways done and yes and yes

Looking_Lost · 08-17-2003, 11:18 AM

Can you ping an external IP such as

ping 64.179.4.146

If you can does your sisters pc have any firewall rules on it created using the internet crushing Lokkit that redhat uses and hates DNS

iptables --list

Or maybe take a step back, deep breathe and start again - you'll get there eventually.

brucedjones · 08-17-2003, 01:32 PM

lol k ill have a go wen ive finished beating both computers with a stick

Mathieu · 08-18-2003, 01:30 PM

brucedjones, I just noticed something in my post.

Did you start iptables ?

At the command line, type: chkconfig --list iptables
3 and 5 should be ON.
If they are not ON, type: chkconfig --level 35 iptables on

To start iptables manually, type: service iptables start

brucedjones · 08-18-2003, 01:45 PM

3 and 5 are on and this is the output of iptables --list
[root@localhost bruce]# iptables --list
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
ACCEPT all -- anywhere anywhere

Chain OUTPUT (policy ACCEPT)
target prot opt source destination
[root@localhost bruce]#

brucedjones · 08-18-2003, 01:49 PM

that console output was for my pc whoops ill go and check it on my pc

brucedjones · 08-18-2003, 02:08 PM

ok my sisters computer is as follows. i can ping 64.179.4.146, i turned OFF lokkit and i did iptables --list as root and it showed that there was no INPUT, FORWARD or OUTPUT......does that help