From owner-freebsd-hackers@FreeBSD.ORG Fri Sep 10 16:18:09 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E9DF1106564A for ; Fri, 10 Sep 2010 16:18:09 +0000 (UTC) (envelope-from ivoras@gmail.com) Received: from mail-qw0-f54.google.com (mail-qw0-f54.google.com [209.85.216.54]) by mx1.freebsd.org (Postfix) with ESMTP id 9C8518FC1F for ; Fri, 10 Sep 2010 16:18:09 +0000 (UTC) Received: by qwg5 with SMTP id 5so1744970qwg.13 for ; Fri, 10 Sep 2010 09:18:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:mime-version:sender:received :in-reply-to:references:from:date:x-google-sender-auth:message-id :subject:to:cc:content-type; bh=K7cmTSn2zEY2FYnSEViGDutWuJVqmSzplqXzLW3ED+U=; b=v9Mrv/XvaCrPsoL5TwwRdmIy3zjDH4Tcv6vuhms73yw+C4PaWzIMksMu7piNlRnqGx 5InmtnjEn+JP4hHRu1K5wRRvm3lm2WZjXNyIGa8ZZhIyVc16CioOLzZIPAt6/yrAIs8K wihXd2Fro3N+dJyehzt3hLQb4gM9KTFLZpH2A= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:cc:content-type; b=SEZzrIjXViSdLJQBAjxIrMysWkQieCMzXw9+mtuC48okpuEfj+lr6sWuzwQl+bTYqV y7WRFOLKlnWQQsrAtLKl+Y4COGckqZucrDofcQNz0SEH1/I6BcD3E+X4EZWACHtsovdM eaoaAxrdCaxDfSKRzT/Jndba3AFj9NRghtVv0= Received: by 10.224.96.146 with SMTP id h18mr551502qan.85.1284135486505; Fri, 10 Sep 2010 09:18:06 -0700 (PDT) MIME-Version: 1.0 Sender: ivoras@gmail.com Received: by 10.229.188.204 with HTTP; Fri, 10 Sep 2010 09:17:46 -0700 (PDT) In-Reply-To: <1009110004520.2000@smasher> References: <1009110004520.2000@smasher> From: Ivan Voras Date: Fri, 10 Sep 2010 18:17:46 +0200 X-Google-Sender-Auth: HZOcYKXUp7vLkWeOaBEXMz8_Xe8 Message-ID: To: Atom Smasher Content-Type: text/plain; charset=UTF-8 Cc: freebsd-hackers@freebsd.org Subject: Re: How to disallow logout X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 10 Sep 2010 16:18:10 -0000 On 10 September 2010 14:11, Atom Smasher wrote: > On Fri, 10 Sep 2010, Ivan Voras wrote: > >> 1) power outage of the server >> 2) power outage on the client >> 3) network problems (ssh or TCP connection drop) >> 4) administrative command (e.g. root executes "killall $shell") >> >> ? >> >> I don't think there is a way to protect from all of those, so any effort >> in protecting from only part of the problem looks useless. > > ======================== > > you forgot cosmic rays, nuclear war and zombie apocalypse, among other > failure modes. *NOTHING* is capable of protecting against everything; a good > solution will most always have pitfalls; as a sysadmin/engineer/manager one > has to either accept the pitfalls or find a more acceptable solution, which > usually means different pitfalls. that doesn't mean a given solution is > useless. On the other hand, things such as power outages, network blackouts and and root security compromises have been statistically shown to appear more often than zombie apocalypses, so I'd guess, though of course without absolute certainty, that those problem should be solved first :) Otherwise, it's just as effective as putting a README file in the home directory saying "please go away" :)