LAN full of public ipv4 addresses - How to filter it?

Posted by sparc86 on Server Fault See other posts from Server Fault or by sparc86
Published on 2012-06-02T18:58:53Z Indexed on 2012/06/02 22:44 UTC
Read the original article Hit count: 155

Filed under:

linux

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iptables

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ipv4

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public-internet

The answer to my question maybe is not that hard but anyways, I do not know what to do.

So, I just got in a new job in a Univerisity and I found out that the network (the LAN) is full of public IP addresses. Seriously, the whole LAN (probably more than 150 hosts) has it' own internet IP address and I don't know how to manage it.

I have a very good experience using iptables (Linux firewall) in a NAT'ed environment. But then how should I proceed in an environment where all my LAN is working with a bunch of public IP addresses? Should I just use the "forward" rules and ignore the NAT rules or is there any other issue in such environment which I should take care?

Can I add a firewall between the router and the LAN in order to produce packet filtering for these public IP addresses in my LAN or will this just not work?

Thanks!

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