Comments on How To Masquerade On Linux (Internet Connection Sharing)

it was really great and use full information and i am really thankfull of the one who prepared and upload this information about internet sharing in linux machin i search lots of sites about this but there were no clear as much as that was in here once again really thanks.

Awesome.

 One small note.  "chkconfig -list iptables" should be "chkconfig --list iptables" (at least on my system, which is normal for all multi-character option names).

To explain (for noobies out there), the command can be "chkconfig -L iptables" or "chkconfig --list iptables".  Note the one dash versus two.  The single-character version, "L" has one dash.  the multi-character version "list", which means the same thing, has two dashes.  This seems to be a standard, as it's held true for every unix command I've used (I think).

 More inportant note:

Remember to configure your LAN adapter (in this case eth0) and give it an ip address.  If you want your computer to be like a router with a 198.168.x.1 style address, use "ifconfig eth0 192.168.0.1 netmask 255.255.255.0 up".  You'll also need to use whatever configuration you system provides you to change the adapters address to 192.168.0.1 so it will be set correctly at bootup.

Thanks, this was really simple and it works 100%. You need credit!

No, it does not work 100%... many of VPNs etc.  cant connect thru this

Great job. The best thing about this tutorial which makes it different from the others on web is that it has taught 'iptables flushing' before setting up IP forwarding.

While I can certainly easily flush the iptables settings as instructed, Debian does not have a "services" command nor a folder /etc/sysconfig. I'll look elsewhere, but I'm torturing myself for the last full year trying to get IP forwarding to work; I must've messed something up in the tables and I can't fix it anymore.

I'm not sure if this is still a problem for you, but in versions of Debian that don't have the "service" command (NOT "serviceS"), I think you can find the needed script in /etc/init.d/iptables, or some such.  Just run a command like this (as root) to save/restart the iptables service:

 /etc/init.d/<NameOfIPtablesScript> save

or

/etc/init.d/<NameOfIPtablesScript> restart

 I hope this solves it for you!

--Dane

For Ubuntu you can use: iptables-save

I have virtual box OS centos in Fedora 14.

I want to access internet from centos to outside,So i have to set MASQUERADE as well as packet forward.

Packet forward is working fine. But MASQUERADE is not working.

I have tried the below command for MASQUERADE

"iptables -t nat -I POSTROUTING -o eth0 -j MASQUERADE"

 Anybody can help me?

is your IP static? if so, try

iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to-source xxx.xxx.xxx.xx

iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to-source xxx.xxx.xxx.xx

this is not forged ip address, when before executing this script internet is coming but after executing internet is not coming .if ping this there is no change ip address pls how to get forged using iptables.

why after i try to run this command chkconfig -list iptables my ouput is "-list: unknown option"???

 did i miss any of the step?

you're missing one "-". It's --list

nice, tq it's work on my PCLINUX OS (server) and UBUNTU (client) 

sad that this is outdated and not working....