Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 25 Sep 1997 20:39:15 +1000
From:      Stephen McKay <syssgm@dtir.qld.gov.au>
To:        Open Systems Networking <opsys@mail.webspan.net>
Cc:        freebsd-chat@freebsd.org, syssgm@dtir.qld.gov.au
Subject:   Re: debian linux ping ? *WARNING LINUX INVOLVED!!* 
Message-ID:  <199709251039.UAA25273@ogre.dtir.qld.gov.au>
In-Reply-To: <Pine.BSF.3.95.970925031328.3496A-100000@orion.webspan.net> from Open Systems Networking at "Thu, 25 Sep 1997 07:22:39 %2B0000"
References:  <Pine.BSF.3.95.970925031328.3496A-100000@orion.webspan.net>

next in thread | previous in thread | raw e-mail | index | archive | help
On Thursday, 25th September 1997, Open Systems Networking wrote:

>While to trying to figure out why my local cable company whos offering
>net access, has such flaky service, i ran across this output of ping and
>cannot figure out WHY it's doing these things. Anyone have an answer?

Ooh!  I like puzzles. :-)

>cypress: {12}ping -v idtswe1
>
>76 bytes from localhost (127.0.0.1): Destination Port Unreachable
>Vr HL TOS  Len   ID Flg  off TTL Pro  cks      Src      Dst Data
> 4  5  00 4400 a758   0 0000  40  11 0024 127.0.0.1  127.0.0.1
>UDP: from port 1254, to port 512 (decimal)

Looks like you were receiving mail and don't have comsat enabled in
/etc/inetd.conf.  And you've got a verbose ping.

>First question is WHY is it showing a packet with a src and dst address as
>127.0.0.1? im not pinging loopback.

Because mail.local tried to talk to biff/comsat, I expect.  Local to local.

>64 bytes from 206.101.232.98: icmp_seq=19 ttl=252 time=61.4 ms
>
>Correct IP address of idtswe1 
>
>64 bytes from lpthomas.winning-edge.com (205.217.148.247): Echo Request
>		^^^^^^^^^^^^^^^^^^^^^^^^
>NOT idtswe1.idir.net
>Whoa hello where did you come from.
>I think debian linux is broke :)
>64 bytes from 206.101.232.98: icmp_seq=117 ttl=252 time=40.0 ms
>64 bytes from 206.101.232.98: icmp_seq=118 ttl=252 time=53.3 ms
>64 bytes from lpthomas.winning-edge.com (205.217.148.247): Echo Request
>		^^^^^^^^^^^^^^^^^^^^^^^
>Whats the deal on that as well?

It looks like linux ping isn't very picky and will display all ICMP traffic
going past.  It is an echo request, not a reply.  Maybe the dude was doing
a broadcast ping.  I expected ping -v on FreeBSD to act the same, but got
nothing special, even as root.  I suppose there could be some kernel
filtering going on, but I seem to be losing interest now. :-)  You'll be
wanting to "Read the Source, Luke"!

Oh well, back to the grind...

Stephen.



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199709251039.UAA25273>