From owner-freebsd-isp@FreeBSD.ORG Mon Mar 29 13:48:02 2004 Return-Path: Delivered-To: freebsd-isp@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id CCCF016A4CE for ; Mon, 29 Mar 2004 13:48:02 -0800 (PST) Received: from whitehall.lin-tech.net (whitehall.lin-tech.net [66.118.35.201]) by mx1.FreeBSD.org (Postfix) with ESMTP id AF12C43D48 for ; Mon, 29 Mar 2004 13:48:02 -0800 (PST) (envelope-from bob@buckhorn.net) Received: from thor.leetrans.com (leetrans.com [65.116.29.218]) by whitehall.lin-tech.net (Postfix) with ESMTP id 9EE7FFF0B; Mon, 29 Mar 2004 15:48:07 -0600 (CST) Received: from buckhorn.net (bob_laptop.leetrans.com [192.168.200.29]) by thor.leetrans.com (Postfix) with ESMTP id 196724F38C; Mon, 29 Mar 2004 15:48:03 -0600 (CST) Message-ID: <4068997A.9000400@buckhorn.net> Date: Mon, 29 Mar 2004 15:47:38 -0600 From: Bob Martin User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Christoph Sold References: <20040329183323.GC51870@telus.net> <200403292211.58942.cs@cheasy.de> In-Reply-To: <200403292211.58942.cs@cheasy.de> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd and fprot cc: freebsd-isp@freebsd.org Subject: Re: tape backup from remote X-BeenThere: freebsd-isp@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Internet Services Providers List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 29 Mar 2004 21:48:02 -0000 Oddly, in the last 15 years or so, I've never had an issue with rdump and latency, even on the old 1.5m networks. IIRC, amanda uses dump too..... B Christoph Sold wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On Monday 29 March 2004 20:33, Sean Ellis wrote: > >>Hello, > > > G'day, > > >>I have a very general question about backing up to tape from a remote >>computer. The tape drive is unfamiliar territory for me, and I'm >>looking for recommendations for a sequence of steps to take. > > > Wise decision. > > >>Both machines are running fbsd 4.*, the local machine is a recent 4.9 >>STABLE, and the tape drive is a Conner CTD800R-S. Will it be >>possible, or advisable, to use a utility to back up over the net >>directly to the tape, or should we be creating a local mirror and >>backing up this? > > > Backing up remotely can yield _very_ unsatisfying results for several > reasons: > - - If there is not enough bandwith, the tape "trashes": After backing up > a few blocks, the tape has to stop, rewind, then re-synchronize and > append to the previously written data. This is _much_ slower than > nominal backup speed. > - - If the network latency is too high, the backup software may get > confused and abort. > - - If the connection is dropped during backup, may tools invalidate the > whole backup. > > There are both commercial as well as open source tools dealing with this > situation. I used amanda (in the ports) to backup multiple remote > clients to one backup machine. Never experienced any data loss during > restore. > > >>I know that these are very basic questions, but I felt that posting >>here in isp might give me a more informed response. > > > Have a look at http://www.thestoragegroup.com/pubs.html , the links > there show many aspects of backup and recovery. > > Another hint, though: DDS (DAT) is not up to the job. I personally > ditched all DDS devices after multiple data loss events being caused by > worn tapes, never properly written tapes, over-aged tapes. Never > happend with DLT, though. > > HTH > - -Christoph Sold > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.2.4 (FreeBSD) > > iD8DBQFAaIMHjGVuYEZ1RPYRAuy+AJ473q/Q5JXWodJu3aeO1y3pQVFT7wCfUkAr > kOiW2k50MoiflSIxUO46+KE= > =tPFi > -----END PGP SIGNATURE----- > _______________________________________________ > freebsd-isp@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-isp > To unsubscribe, send any mail to "freebsd-isp-unsubscribe@freebsd.org"