Re: iptables: DROP or REJECT?

From: Grant (
Date: 10/07/05

  • Next message: suze: "iptables disables outbound traffic"
    Date: Sat, 08 Oct 2005 07:54:16 +1000

    On Fri, 07 Oct 2005 08:17:34 -0400, Lew Pitcher <> wrote:
    >FWIW, my firewall rules explicitly DROP any packets from the internet to
    >my LAN that don't meet my requirements for passage (ie trying to access
    >priviledged ports, coming from a blacklisted IP address, etc).

    Yes, I have a blacklist too, just DROP 'em, part of reducing traffic
    from stupid web-crawlers, drop by entire 'whois' CIDR block.

    >OTOH, my firewall rules explicitly REJECT any packets from my LAN to the
    >internet that don't meet my requirements for passage (i.e. trying to
    >send to a private IP range or trying to send one of the ICMP messages
    >I've blacklisted).

    Was under impression one could only _drop_ ICMPs, not reject them,
    per RFC <mumble>.

    As far as rejecting goes, when I tested various reject options I found
    some types of reject message types do increase unwanted traffic, the
    current 'be reasonable then drop' workings has been in place for some
    time, I become less aware of the firewall needing change.


  • Next message: suze: "iptables disables outbound traffic"

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