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Date: Wed, 10 Jan 2007 09:38:51 -0600
To: Nejc =?iso-8859-1?Q?=8Akoberne?= <nejc@skoberne.net>, questions@freebsd.org
From: Derek Ragona <derek@computinginnovations.com>
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Subject: Re: Simple DoS
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Your client caused their own DOS by making it impossible to route network=
=20
traffic.  Basically causing an arp storm.  In simple terms, don't do that.

Not much you can do with dumb clients, except reward them with a bill for=
=20
their actions.

         -Derek


At 08:53 AM 1/10/2007, Nejc =8Akoberne wrote:
>Hello,
>
>yesterday one of our clients did something interesting (stupid): they
>connected both ends of an UTP cable to the same switch, to which our
>FreeBSD server was also connected. The server was immediately completely
>unresponsive from yesterday evening until this morning, when our tech
>guy went there to see what the problem was. Even when they rebooted
>the FreeBSD machine, it wouldn't boot normally - disk I/O was very
>busy and everything was happening unusably slow. After the disconnect
>from that switch, everything went back to normal.
>
>Any ideas how to prevent such situations in the future? (I would like
>to do it on the server side, not on the "user side".)
>
>Thanks,
>Nejc
>
>

--=20
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