tcpdump output with iptables REJECT policy enabled

Posted by Pablo Santa Cruz on Server Fault See other posts from Server Fault or by Pablo Santa Cruz
Published on 2011-02-09T14:45:19Z Indexed on 2011/02/09 15:27 UTC
Read the original article Hit count: 385

Filed under:

firewall

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iptables

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tcp

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tcpdump

Hi all,

Quick question.

I have a firewall with these simple rules:

iptables -A INPUT -p tcp -s 127.0.0.1/32 --dport 6000 -j ACCEPT
iptables -A INPUT -p tcp -s 192.168.16.20/32 --dport 6000 -j ACCEPT
iptables -A INPUT -p tcp --dport 6000 -j REJECT

Now, suppose I am using TCPDUMP like this:

tcpdump port 6000

And I have host 192.168.16.21 trying to connect to port 6000.

My question is: will/should tcpdump output some packages coming from 192.168.16.21?

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