nanog mailing list archives
Re: SMURF amplifier block list
From: Pete Ashdown <pashdown () xmission com>
Date: Mon, 20 Apr 1998 09:53:34 -0600 (MDT)
jlixfeld () idirect ca said once upon a time:
You could always "deny icmp any aaa.bbb.ccc.ddd www.ccc.nnn.mmm log" on your cores. Deny ICMP from critical portions of your network. Create a little script which tail -fs the log, parses it, sorts it and counts it. If the script counts more then xxx hits on a certain IP or a certain number of IPs on your network from the same source or a multiple sources on the same network, you have your upstream. Once you have them, you can call them and ask them to do the same until you find the real source.
You might want to stick in an "echo-reply" before the log. This will specifically block the smurf, but won't affect any of the other ICMP which does have a useful purpose. This of course will stop any of the blocked addresses from doing outside pings or traceroutes as well.
Current thread:
- Re: SMURF amplifier block list, (continued)
- Re: SMURF amplifier block list Alex P. Rudnev (Apr 20)
- Spoofed Packet Tracker (Was Re: SMURF amplifier block list) Jared Mauch (Apr 20)
- Message not available
- Re: SMURF amplifier block list Jay R. Ashworth (Apr 19)
- Re: SMURF amplifier block list jlixfeld (Apr 20)
- Re: SMURF amplifier block list Dean Anderson (Apr 18)
- Re: SMURF amplifier block list Alex P. Rudnev (Apr 18)
- Re: SMURF amplifier block list Dean Anderson (Apr 18)
- Re: SMURF amplifier block list Alex P. Rudnev (Apr 18)
- Re: SMURF amplifier block list Dean Anderson (Apr 18)
- Re: SMURF amplifier block list jlixfeld (Apr 20)
- Re: SMURF amplifier block list Pete Ashdown (Apr 20)
- Re: SMURF amplifier block list Jason Lixfeld (Apr 24)
- Filtering ICMP (Was Re: SMURF amplifier block list) Mark Whitis (Apr 20)
- Re: Filtering ICMP (Was Re: SMURF amplifier block list) Marc Slemko (Apr 20)
- Re: Filtering ICMP (Was Re: SMURF amplifier block list) Michael Dillon (Apr 20)
- Re: Filtering ICMP (Was Re: SMURF amplifier block list) Mark Whitis (Apr 22)
- Re: Filtering ICMP (Was Re: SMURF amplifier block list) Michael Dillon (Apr 20)
- Re: Filtering ICMP (Was Re: SMURF amplifier block list) Michael Shields (Apr 22)
- Re: Filtering ICMP (Was Re: SMURF amplifier block list) Alex P. Rudnev (Apr 21)
- Re: Filtering ICMP (Was Re: SMURF amplifier block list) D'Arcy J.M. Cain (Apr 22)
- Re: Filtering ICMP (Was Re: SMURF amplifier block list) Alex P. Rudnev (Apr 21)