Re: iptables -A or iptables -I?

[Juan Carlos Inostroza <jci@tux.cl>]

On Tue, 2004-10-19 at 18:42 +0200, Martin G.H. Minkler wrote:
> Alohá!
> 
> Just out of curiosity - which is faster (what kind of datastructure does 
> iptables use)?
> 
> a) iptables -A <chain> <rule>
> b) iptables -I <chain> 1 <rule>
> 
> Maybe this is rather a kernelspace question and should be directed to 
> that mailing list?

Iptables -I inserts the chain at the top of the rules.
Iptables -A adds it to the bottom of the rules.

so,

iptables -A INPUT -p icmp -j DROP
iptables -A INPUT -p tcp -j DROP
iptables -I INPUT -p udp -j DROP

is the same as

iptables -A INPUT -p udp -j DROP
iptables -A INPUT -p icmp -j DROP
iptables -A INPUT -p tcp -j DROP

Cheers!

-- 
Juan Carlos Inostroza O.
Registered Linux User #246002
jci@tux.cl - http://www.tux.cl - http://foros.tux.cl
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