How to make a computer invisible
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Hello folks,
how do I really make a computer totally invisibly as it would be when it does not exist?
It is clear, that the simplest solution is to DROP all incoming packets, but what's about (R)ARP packets? Can they be blocked anyway?
TIA,
Tom
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Quoted 3 lines · Thomas Preissler
how do I really make a computer totally invisibly as it would be when it does not exist?
Leave the power switch in the "off" position. ;-)
Quoted 2 lines
It is clear, that the simplest solution is to DROP all incoming packets,
Actually, dropping packets is a clear indication that you do in fact have a firewall protecting one or more systems. Its the only condition which will cause ICMP error packets to not be returned consistently.
You would be better off rejecting with host unreachables. then your firewall looks like a simple router, and the host in question looks like it is powered down.
HTH,
C
Quoted 4 lines · Leonardo Rodrigues Magalhães
AFAIK, iptables can use some 'layer 2' information such as MAC Address
for doing some filtering in some tables, but it CANT be used for filtering those 'layer 2' packets. That means iptables CANNOT modify ARP/RARP behavior.
You can choose to ignore them, by initializing the interface with a 'ifconfig -arp', but this will disable all ARP functionality forcing you to use manual entries. That's sort of like filtering. ;-)
C
AFAIK, iptables can use some 'layer 2' information such as MAC Address
for doing some filtering in some tables, but it CANT be used for filtering those 'layer 2' packets. That means iptables CANNOT modify ARP/RARP behavior.
Sincerily,
Leonardo Rodrigues
----- Original Message -----
From: "Thomas Preissler" <[email protected]>
To: "netfilter-user Mailinglist" <[email protected]>
Sent: Sunday, November 30, 2003 3:12 PM
Subject: How to make a computer invisible
Quoted 8 lines
Hello folks,
how do I really make a computer totally invisibly as it would be when it does not exist?
It is clear, that the simplest solution is to DROP all incoming packets, but what's about (R)ARP packets? Can they be blocked anyway?
Some new informations .....
iptables really cannot do that. But you should take a look at:
http://sourceforge.net/projects/ebtables/
go to Files link and you'll see 'arptables' ..... guess what it does ???
:)
----- Original Message -----
From: "Leonardo Rodrigues Magalhães" <[email protected]>
To: "Thomas Preissler" <[email protected]>; "netfilter-user Mailinglist" <[email protected]>
Sent: Sunday, November 30, 2003 4:32 PM
Subject: Re: How to make a computer invisible
Quoted 16 lines
AFAIK, iptables can use some 'layer 2' information such as MAC Address
for doing some filtering in some tables, but it CANT be used for filtering those 'layer 2' packets. That means iptables CANNOT modify ARP/RARP behavior.----- Original Message -----
From: "Thomas Preissler" <[email protected]>
To: "netfilter-user Mailinglist" <[email protected]>
Sent: Sunday, November 30, 2003 3:12 PM
Subject: How to make a computer invisibleQuoted 5 lines
how do I really make a computer totally invisibly as it would be when it does not exist?
It is clear, that the simplest solution is to DROP all incoming packets, but what's about (R)ARP packets? Can they be blocked anyway?