Re: Confused about ping...

From: Peter Gordon (
Date: 10/06/05

  • Next message: Robin Laing: "Re: Confused about ping..."
    Date: Thu, 6 Oct 2005 15:43:52 -0500 (CDT)
    To: "For users of Fedora Core releases" <>

    > $ ping
    > PING ( 56(84) bytes of data.
    > From icmp_seq=0 Packet filtered
    > From icmp_seq=1 Packet filtered
    > From icmp_seq=2 Packet filtered
    > From icmp_seq=3 Packet filtered
    > What does "Packet filtered" mean?

    Ping works by sending an ICMP "Echo" data packet to the
    specified host, and waiting for its ICMP "Echo Reply" data
    packet (which, if successful, should be exactly the same as
    the data sent in the original Echo packet). Many system
    adminstrators filter this type of packet on their firewalls,
    though, as ICMP ping requests can be used by malicious users to
    cause a DoS (Denial of Service) on an otherwise-functional
    system. That's probably what you're seeing.

    Hope that helps!

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