From owner-freebsd-questions@freebsd.org Wed Apr 25 17:54:06 2018 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id CE528FAB7F2 for ; Wed, 25 Apr 2018 17:54:06 +0000 (UTC) (envelope-from freebsd-doc@fjl.co.uk) Received: from bs1.fjl.org.uk (bs1.fjl.org.uk [84.45.41.196]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "bs1.fjl.org.uk", Issuer "bs1.fjl.org.uk" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 5A7587D511 for ; Wed, 25 Apr 2018 17:54:05 +0000 (UTC) (envelope-from freebsd-doc@fjl.co.uk) Received: from roundcube.fjl.org.uk (localhost [127.0.0.1]) by bs1.fjl.org.uk (8.14.4/8.14.4) with ESMTP id w3PHm0aX079515 for ; Wed, 25 Apr 2018 18:48:00 +0100 (BST) (envelope-from freebsd-doc@fjl.co.uk) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 25 Apr 2018 18:48:00 +0100 From: Frank Leonhardt To: Freebsd Questions Subject: Backing up to tape Message-ID: <4a136190a89f631efabcc6fb803e8119@roundcube.fjl.org.uk> X-Sender: freebsd-doc@fjl.co.uk User-Agent: Roundcube Webmail/0.9.2 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Apr 2018 17:54:07 -0000 Old LTO drives are cheap and offer a good $/Gb. And I could do with some archiving. But it's been a while since I used tape (System V IIRC). Are my assumptions correct? If I plug a SAS drive in to an HBA it'll just appear as /dev/sa0 (or similar) - right? Then I can backup everything with tar -cf /dev/sa0 /* - right? Well I could if my HD was small or the tape was big, as the tar documentation says "There is not yet any support for multi-volume archives." Does the tape driver take care of this (i.e. "Insert Tape 2 and press a key") or does it just bomb? I like tar for archiving stuff, but is dump/restore the way to go? Probably not, because you can't specify files really. And I'm probably more likely to backup ZFS datasets these days, so would be relying on the tape driver to handle multi-volume tape sets. One idea I have is to write a very quick and dirty program and pipe the output of tar to it, and have it write to the tape unit - pausing for tape changes. This is so obvious that it must already exist, or be a bad idea for a subtle reason I haven't spotted. Is anyone using tape able to confirm any of this one way or another? Thanks, Frank.