"Bad argument" when I try to set a iptables command

Question

I'm trying to run the following command:

sudo /usr/sbin/iptables -A INPUT -m state --state NEW -i ! wlan0 -j ACCEPT

But i got this error:

Bad argument wlan0' Tryiptables -h' or 'iptables --help' for more information.

I don't know what is wrong, the man says that you have to put a "!" before the conection adapter (in this case is wlan0)

Solution

You should try this command in this form:

sudo /usr/sbin/iptables -A INPUT -m state --state NEW ! -i wlan0 -j ACCEPT

But be sure, that interface wlan0 is up:

sudo ifconfig wlan0 up

Comments

[user9517]

What are you actually trying to achieve ?

[Mr_LinDowsMac]

@Iain Something about Masquerading ibiblio.org/pub/linux/docs/HOWTO/other-formats/html_single/…

[Mr_LinDowsMac]

I'm trying to resolve the problem posted here: serverfault.com/questions/417729/…

[user9517]

Your question is off topic for Serverfault because it doesn't appear to relate to servers/networking or desktop infrastructure in a professional environment. It may be on topic for Superuser but please search their site for similar questions that may already have the answer you're looking for. It may also be on topic for raspberrypi.stackexchange.com

[Mr_LinDowsMac]

Ok, i'll post it there.

[Mr_LinDowsMac]

I applied the rule but didn't fix my problem