From owner-freebsd-questions@FreeBSD.ORG Wed Aug 24 21:37:08 2005 Return-Path: X-Original-To: questions@freebsd.org Delivered-To: freebsd-questions@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E9DC016A41F for ; Wed, 24 Aug 2005 21:37:08 +0000 (GMT) (envelope-from djh@nebcorp.com) Received: from ratchet.nebcorp.com (ratchet.nebcorp.com [205.217.153.72]) by mx1.FreeBSD.org (Postfix) with ESMTP id AC67A43D45 for ; Wed, 24 Aug 2005 21:37:08 +0000 (GMT) (envelope-from djh@nebcorp.com) Received: by ratchet.nebcorp.com (Postfix, from userid 1014) id 60FDBD9829; Wed, 24 Aug 2005 14:37:08 -0700 (PDT) Date: Wed, 24 Aug 2005 14:37:08 -0700 From: Danny Howard To: Scott Mitchell Message-ID: <20050824213708.GT51748@ratchet.nebcorp.com> References: <20050819141535.GA62513@lohi.local> <20050823182133.GF51748@ratchet.nebcorp.com> <20050823112716.U26292@wolf.pjkh.com> <20050824113237.GA68101@llama.fishballoon.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050824113237.GA68101@llama.fishballoon.org> User-Agent: Mutt/1.4.2.1i X-Loop: djhoward@uiuc.edu Cc: Ilari Laitinen , questions@freebsd.org Subject: Re: dump(8), incremental backups, Tower of Hanoi sequence, don't get it 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: Wed, 24 Aug 2005 21:37:09 -0000 On Wed, Aug 24, 2005 at 12:32:38PM +0100, Scott Mitchell wrote: > Another useful rsync option is --link-dest: > > --link-dest=DIR > This option behaves like --copy-dest, but unchanged files are > hard linked from DIR to the destination directory. The files > must be identical in all preserved attributes (e.g. permissions, > possibly ownership) in order for the files to be linked > together. > > I use this to rsync each backup into a new directory on the backup volume, > named for the date of the backup. The result is a directory for each backup > run, apparently containing every file from the source tree - but most of them > are just hard links to some previous backup. This saves a *lot* of disk > space as you only ever copy files that have changed since the last backup. > You also have the complete file tree for each backup, so it's trivial to > restore the version of a file that existed on any particular date. All this great discussion got me researchinng. I haven't tried this out but it looks like rsnapshot integrates a lot of features like this into a single configurable, cronable script. It is in ports as well. A lot of systems make use of cp -al ... well, for us FreeBSD people that means gcp from coreutils. rsnapshot looks like a lightweight, OS/FS-portable method of building rotating filesystem-wide snapshots via hardlinks, but can be made to operate on limited sets of directories, etc. It can create local snaphots of remote directories, but not, apparently, remote copies of local directories. One trick I gleaned from http://burd.info/gary/2003/03/snapshot-backup-using-rsync-and-ssh.html is to invoke rsync with --rsync-path which points to a script which performs maintenence functions and then passes off to rsync proper, so you could probably set up a client-triggered rsnapshot configuration if you were, say, doing backups of a Windows laptop client. :) -danny -- http://dannyman.toldme.com/