From owner-freebsd-fs@FreeBSD.ORG Thu Jun 9 19:38:17 2011 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 61B51106566B for ; Thu, 9 Jun 2011 19:38:17 +0000 (UTC) (envelope-from danny@dannysplace.net) Received: from mailgw.dannysplace.net (mailgw.dannysplace.net [204.109.56.184]) by mx1.freebsd.org (Postfix) with ESMTP id 29CCD8FC13 for ; Thu, 9 Jun 2011 19:38:16 +0000 (UTC) Received: from localhost ([127.0.0.1]) by mailgw.dannysplace.net with esmtpsa (TLSv1:CAMELLIA256-SHA:256) (Exim 4.76 (FreeBSD)) (envelope-from ) id 1QUklM-0007Rv-EY for freebsd-fs@freebsd.org; Fri, 10 Jun 2011 05:19:29 +1000 Message-ID: <4DF11BB8.5030805@dannysplace.net> Date: Thu, 09 Jun 2011 21:15:04 +0200 From: Dan Carroll User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.17) Gecko/20110414 Thunderbird/3.1.10 MIME-Version: 1.0 To: freebsd-fs@freebsd.org Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: danny@dannysplace.net X-Authenticated-User: danny X-Authenticator: plain X-Exim-Version: 4.76 (build at 08-Jun-2011 18:40:49) X-Date: 2011-06-10 05:19:28 X-Connected-IP: 127.0.0.1:10349 X-Message-Linecount: 21 X-Body-Linecount: 10 X-Message-Size: 896 X-Body-Size: 456 X-Received-Count: 1 X-Recipient-Count: 1 X-Local-Recipient-Count: 1 X-Local-Recipient-Defer-Count: 0 X-Local-Recipient-Fail-Count: 0 X-SA-Exim-Connect-IP: 127.0.0.1 X-SA-Exim-Mail-From: danny@dannysplace.net X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on damka.dannysplace.net X-Spam-Level: X-Spam-Status: No, score=-2.9 required=5.0 tests=ALL_TRUSTED,BAYES_00 autolearn=ham version=3.3.1 X-SA-Exim-Version: 4.2 X-SA-Exim-Scanned: Yes (on mailgw.dannysplace.net) Subject: Getting access to checksums. X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: fbsd@dannysplace.net List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Jun 2011 19:38:17 -0000 I'm currently working on a system that monitors file changes. I'd like to calculate the checksums on each file both to see if a change has occured as well as looking for duplicate files. I'm not sure what algorithm I'll end up using but I was wondering if it was possible to get access to ZFS' checksumming? Does it happen on a file level or is it block level only? And if it does, is there an easy way to obtain this information from the system? -D