From mboxrd@z Thu Jan  1 00:00:00 1970
From: Antony Stone <Antony@Soft-Solutions.co.uk>
Subject: Re: why do we need to allow all traffic from lo interface???
Date: Tue, 29 Oct 2002 08:52:23 +0000
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On Tuesday 29 October 2002 1:09 am, Tan Ming Han wrote:

> hi,
>    I seen some examples allowing all traffic (in INPUT and OUTPUT) from lo
> interface. Why is it so? Is it becos of the local XWindow connection?

X requires this, yes; there are also certain other applications which use 
things like rpc calls or ident lookups.   A simple way to find out what 
traffic goes across the lo interface is to log it for a while:

iptables -A INPUT -i lo -j LOG --log-prefix="In-lo: "
iptables -A INPUT -i lo -j ACCEPT

Antony.

-- 

Windows: just another pane in the glass.