Newby to IP tables - How do I see what I have for a firewall ?  Nmap does not seem to be "accurate"

Posted on 2009-12-28
Last Modified: 2013-12-06
I am using the lastest redhat 5.4.  When I look at my iptables -L I have a short firewall and it does not let much in.  If I do an Nmap, I get more ports than the firewall allows.

If I want to see what I really have for a firewall, I can test ALL Ports individually or is there some way to do this easly ?  I thought that if I blocked a port in iptables, it would not show up in nmap.  

Oh, keep an eye on my user id today, I will be asking a bunch of silly questoins that are easy pickings for the right person :)  Today is a "study iptables" day :)

Question by:TIMFOX123
    LVL 29

    Accepted Solution

    A good free tool to use for setting up IPTables is Firewall Builder (

    Firewall Builder consists of an object-oriented GUI and a set of policy compilers for various firewall platforms. In Firewall Builder, a firewall policy is a set of rules; each rule consists of abstract objects that represent real network objects and services (hosts, routers, firewalls, networks, protocols). Firewall Builder helps users maintain a database of objects and allows policy editing using simple drag-and-drop operations.

    As a bonus (and to make it easier), if you have an existing IPTables firewall setup, Firewall Builder GUI has built-in policy importer that can import iptables policy saved with iptables-save script.
    LVL 4

    Assisted Solution

    run service iptables status to get the current firewall that is active on the system.

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