From owner-freebsd-isp Thu Jan 23 20:43:40 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id UAA06589 for isp-outgoing; Thu, 23 Jan 1997 20:43:40 -0800 (PST) Received: from tok.qiv.com (root@[204.214.141.211]) by freefall.freebsd.org (8.8.5/8.8.5) with ESMTP id UAA06582 for ; Thu, 23 Jan 1997 20:43:35 -0800 (PST) Received: (from uucp@localhost) by tok.qiv.com (8.7.5/8.7.3) with UUCP id WAA16755; Thu, 23 Jan 1997 22:30:32 -0600 Received: from localhost (jdn@localhost) by acp.qiv.com (8.7.5/8.7.3) with SMTP id VAA00727; Thu, 23 Jan 1997 21:34:42 -0600 (CST) X-Authentication-Warning: acp.qiv.com: jdn owned process doing -bs Date: Thu, 23 Jan 1997 21:34:41 -0600 (CST) From: "Jay D. Nelson" To: Luigi Rizzo cc: rg@gds.de, freebsd-isp@freebsd.org Subject: Re: Ping DUP In-Reply-To: <199701231231.NAA21897@labinfo.iet.unipi.it> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-isp@freebsd.org X-Loop: FreeBSD.org Precedence: bulk I saw this on our subnet when a network printer adapter mysteriously changed it's IP address to the broadcast address. Some questions you never want to ask for fear of the answer -- and this was one! -- Jay On Thu, 23 Jan 1997, Luigi Rizzo wrote: ->> route add 194.231.79.60 localhost ->> ->> Now, when I ping this address from another network every ip-packet ->> get duplicated: ->> ->> PING 194.231.79.60 (194.231.79.60): 56 data bytes ->> 64 bytes from 194.231.79.60: icmp_seq=0 ttl=251 time=59.921 ms ->> 64 bytes from 194.231.79.60: icmp_seq=0 ttl=251 time=69.929 ms (DUP!) ->> 64 bytes from 194.231.79.60: icmp_seq=1 ttl=251 time=60.104 ms ->> 64 bytes from 194.231.79.60: icmp_seq=1 ttl=251 time=70.113 ms (DUP!) ->> 64 bytes from 194.231.79.60: icmp_seq=2 ttl=251 time=60.108 ms ->> 64 bytes from 194.231.79.60: icmp_seq=2 ttl=251 time=70.071 ms (DUP!) ->> 64 bytes from 194.231.79.60: icmp_seq=3 ttl=251 time=50.142 ms ->> 64 bytes from 194.231.79.60: icmp_seq=3 ttl=251 time=60.133 ms (DUP!) ->> ^C --- ->> 194.231.79.60 ping statistics --- 4 packets transmitted, 4 packets ->> received, +4 duplicates, 0% packet loss round-trip min/avg/max = ->> 50.142/62.565/70.113 ms # ->> ->> There are no DUPs when pinging from within the same net. ->> ->> I did not have this problem with FreeBSD 2.1.5 nor with 3.0 and a ->> NE2000 clone. ->> ->> Could it be a bug in the vx0 driver or did I misconfigure something? -> ->most likely you have two paths to/from your host, and either the ping ->request or the response are duplicated. It i also interesting to note ->the 10ms difference between the dups -- although I cannot tell where ->this difference comes from! -> -> Luigi ->-----------------------------+-------------------------------------- ->Luigi Rizzo | Dip. di Ingegneria dell'Informazione ->email: luigi@iet.unipi.it | Universita' di Pisa ->tel: +39-50-568533 | via Diotisalvi 2, 56126 PISA (Italy) ->fax: +39-50-568522 | http://www.iet.unipi.it/~luigi/ ->_____________________________|______________________________________ ->