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From: Jeffrey Laramie <JALaramie@Loudoun-Fairfax.com>
To: Netfilter <netfilter@lists.netfilter.org>
Subject: Re: MAC Block for the DHCP via iptables
Date: Mon, 17 Nov 2003 12:42:33 -0500	[thread overview]
Message-ID: <3FB90889.9040804@Loudoun-Fairfax.com> (raw)
In-Reply-To: <200311171702.hAHH2pj22305@agate.rockstone.co.uk>

Antony Stone wrote:

>On Monday 17 November 2003 4:35 pm, Chandana Bandara wrote:
>
>  
>
>>Hi     Mr.Antony & ALL ,
>>
>>iptables -P INPUT DROP
>>iptables -P FORWARD DROP
>>iptables -P OUTPUT DROP.........only with those policies ,
>>should block the all incomming , outgoing from the machine ?????
>>    
>>
>
>Assuming you have flushed the rules as well, with:
>
>iptables -F INPUT
>iptables -F FORWARD
>iptables -F OUTPUT
>
>then no IP traffic will be allowed into, out of, or through, the machine.
>
>  
>

Chandana, Antony is making a theoretical point here. Your loopback interface uses the OUTPUT chain and dropping every OUTPUT packet could cause some unexpected problems. I wouldn't recommend doing this. If you ever really wanted to block *all* traffic just unplug the network card(s). It's a lot easier and 100% secure. I hope Mr. Curleybaces reads this too or he could be in for a big surprise :-)

Jeff



  reply	other threads:[~2003-11-17 17:42 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-11-17 16:35 MAC Block for the DHCP via iptables Chandana Bandara
2003-11-17 17:02 ` Antony Stone
2003-11-17 17:42   ` Jeffrey Laramie [this message]
2003-11-17 17:57     ` Antony Stone
2003-11-17 18:17       ` Jeffrey Laramie

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