Re: New ICMP limits

From: Andre Oppermann (
Date: 12/08/04

  • Next message: Scott M. Ferris: "Re: UCARP support for FreeBSD"
    Date: Wed, 08 Dec 2004 15:53:07 +0100
    To: Michal Mertl <>

    Michal Mertl wrote:
    > Hello,
    > I think some network administrators may want to set different maximum rate
    > for different types of ICMP replies. Currently the limit
    > net.inet.icmp.icmplim is enforced independently for the following cases -
    > ICMP echo-reply, ICMP timestamp reply, ICMP port unreachable (generated as a
    > response to a packet received on a UDP port with no listening application).
    > It's in addition a bit misused (or at least misnamed) for limiting sending
    > of TCP reset packets on closed and open ports.
    > Andre Oppermann wrote a patch which adds support for limiting the sending of
    > ICMP host unreachable messages. These are generated by a router when it
    > can't send the packet to the destination, such as when it's about to send to
    > an unused IP address on a directly connected network.


    I'll take care of this but I'm busy right now. Look into it later this week.

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  • Next message: Scott M. Ferris: "Re: UCARP support for FreeBSD"

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