From owner-freebsd-stable@FreeBSD.ORG Tue Nov 23 23:32:17 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AC4CB1065674 for ; Tue, 23 Nov 2010 23:32:17 +0000 (UTC) (envelope-from areilly@bigpond.net.au) Received: from nskntmtas02p.mx.bigpond.com (nskntmtas02p.mx.bigpond.com [61.9.168.140]) by mx1.freebsd.org (Postfix) with ESMTP id 461938FC17 for ; Tue, 23 Nov 2010 23:32:16 +0000 (UTC) Received: from nskntotgx04p.mx.bigpond.com ([124.188.161.100]) by nskntmtas02p.mx.bigpond.com with ESMTP id <20101123233215.XJLU3622.nskntmtas02p.mx.bigpond.com@nskntotgx04p.mx.bigpond.com>; Tue, 23 Nov 2010 23:32:15 +0000 Received: from johnny.reilly.home ([124.188.161.100]) by nskntotgx04p.mx.bigpond.com with ESMTP id <20101123233215.QEYY6348.nskntotgx04p.mx.bigpond.com@johnny.reilly.home>; Tue, 23 Nov 2010 23:32:15 +0000 Date: Wed, 24 Nov 2010 10:31:59 +1100 From: Andrew Reilly To: Thomas Ronner Message-ID: <20101123233159.GA11081@johnny.reilly.home> References: <20101122113541.GA74719@johnny.reilly.home> <4CEA8BA6.7080009@kc8onw.net> <20101123124543.GA4751@johnny.reilly.home> <4CEBB9E1.6040403@ronner.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4CEBB9E1.6040403@ronner.org> User-Agent: Mutt/1.4.2.3i X-RPD-ScanID: Class unknown; VirusThreatLevel unknown, RefID str=0001.0A150204.4CEC4EFF.0065,ss=1,fgs=0 Cc: freebsd-stable@freebsd.org Subject: Re: ZFS backups: retrieving a few files? X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 23 Nov 2010 23:32:17 -0000 On Tue, Nov 23, 2010 at 01:56:01PM +0100, Thomas Ronner wrote: > On 11/23/10 1:45 PM, Andrew Reilly wrote: > >No, I don't like tar, rsync and friends for backups: they don't > >deal well with hard links, special files or sparse files. > > rsync -avHxS --delete --numeric-ids /src/. /dst/. > > Handles sparse files (S) and hard links (H). Never had any trouble with > special files. What sort of special files are not handled correctly by > rsync? I'd like to know because I'm relying on rsync for backups for > years on my home network. I remember having problems with hard links, but it's possible that I wasn't using rsync correctly. Of special files, I don't remember non-dump backups doing well with the unix-domain sockets that were liberally used and tricky to set up right for djb's daemon-tools. Most uses of sockets put them in /tmp, don't get backed up, and they don't need to persist. Dan puts them in /var, and they're expected to persist across reboots, which means they need to be backed-up. Maybe rsync and modern tar handle these OK, but I remember at least one of them getting wedged just trying to read one as a file. The special files in /dev used to be a problem too, but that's gone away, now that we have devfs. I really like dump/restore. I expect that I will miss them. Cheers, -- Andrew