NAT and Source Address

Posted on 2008-11-16
Last Modified: 2013-12-25
Say I want to block a website at If I am using NAT on my network how would I define that traffic? What would the source addres be?  Would I have to block with a firewall or access list before the traffic is NATed?
Question by:jlgray48
    LVL 3

    Assisted Solution

    on external router interface create a deny ip access list and on the internal router creat a loopback adapter and point all internal traffic to this address.

    this will break communication in both directions.

    LVL 18

    Accepted Solution

    If users are accessing it via DNS name (like for HTTP/s or FTP) then simply make a bogus A record and blackhole it...    Easier than messing with routers..

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