From owner-freebsd-questions@FreeBSD.ORG Mon Aug 10 15:22:01 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 56C57106564A for ; Mon, 10 Aug 2009 15:22:01 +0000 (UTC) (envelope-from jhall@socket.net) Received: from mf5.socket.net (mf5b.socket.net [216.106.26.210]) by mx1.freebsd.org (Postfix) with ESMTP id 38BC18FC15 for ; Mon, 10 Aug 2009 15:22:00 +0000 (UTC) Received: from [10.129.40.203] (216.106.12.14.reverse.socket.net [216.106.12.14]) by mf5.socket.net (Postfix) with ESMTP id DE69A62F1E for ; Mon, 10 Aug 2009 10:21:59 -0500 (CDT) Message-Id: <6206A242-7226-48E3-8D09-A1D3A651F2A8@socket.net> From: Jay Hall To: freebsd-questions@freebsd.org Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v935.3) Date: Mon, 10 Aug 2009 10:21:58 -0500 X-Mailer: Apple Mail (2.935.3) Subject: Backup Size X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Aug 2009 15:22:01 -0000 I am sure there is an easy explanation for this, but I cannot find it. I am backing up my /etc directory using the following command. tar -cvf - /etc | dd of=/dev/nsa1 obs=10240 When the command completes, I receive the following message. 3080+0 records in 154+0 records out 1576960 bytes transferred in 0.179921 secs (8764740 bytes/sec) What concerns me is when running du -h /etc, the size of the folder is reported as 1.7M. Is the number of bytes written to the tape less than the reported size of the directory because of the way the files are written to the tape? If so, how can the amount of space used be calculated? Thanks for your help. Jay