[sclug] Irritating networking problem

[Simon Huggins]

On Tue, Sep 04, 2007 at 10:16:26AM +0100, David Given wrote:
> But when I actually try to *use* it, I just get:

> PING 172.16.100.2 (172.16.100.2) 56(84) bytes of data.
> ping: sendmsg: Operation not permitted

> ...which is not something that I've ever seen before.

> Investigation reveals that if I reboot the machine, it starts working,
> but stops again if I change the IP address. This appears to point to
> firewalling issues, and Ubuntu has, indeed, installed a bunch of
> iptables rules without me asking it to.

> Does this seem like a reasonable conclusion? Given that I already have a
> perfectly good real firewall attached to my server, does anyone know how to
> turn *off* a Linux firewall? Completely? Would this help?

Well iptables -L will show you what it's done and you might be better
off fixing the firewall than removing it entirely.

Anyway if you really do want to you should change the default policy to
ACCEPT and remove all the rules something like:
iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT
iptables -F
iptables -X

Have a look at the manpage to work out what it does.

-- 
----------(   "Clear?" - Holly. "No." - Lister. "Tough." -   )----------
Simon ----(                      Holly.                      )---- Nomis
                             Htag.pl 0.0.22
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