DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:date:from:to:subject:message-id:in-reply-to
	:references:mime-version:content-type:content-transfer-encoding;
	 q=dns; s=default; b=F5UUgV1KBPaJQ3Ib58bYZ10OV3mejBxL54cnnKO30Lr
	EuKY2r6jAvPBWSgA2UaOAWiNYLkx27rp1lldEhThw5yW8tYVpOtxY4xVLnTPQGMr
	qGEAjtbl0rkMJ5Zw1uFn/72cXjfLxuiwr8rxruOWvAUrn5PRWfcW+xW2/Oq3zon8
	=
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Date: Sun, 22 Dec 2013 21:55:04 +0400
From: Mikhail Usenko <mikeus AT nm DOT ru>
To: cygwin AT cygwin DOT com
Subject: Re: "Device or resource busy" during read (rsync)
Message-Id: <20131222215504.d590c9d0fad214acdeaf6bf5@nm.ru>
In-Reply-To: <C14924774373A047BE1F8EF948922F493EEF3E6A@UM-MBX-T03.um.umsystem.edu>
References: <C14924774373A047BE1F8EF948922F493EEF3E6A AT UM-MBX-T03 DOT um DOT umsystem DOT edu>
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit

On Sun, 22 Dec 2013 00:02:10 +0000
Winkel, Richard J. <...> wrote:

> I have a hard time believing this is an unusual question but I swear 
> I've been googling everywhere without an answer!  :)
> I'm using rsync (under cygwin) to backup windows servers to a linux box 
> and it's working wonderfully, except that if a file is open rsync can't 
> access it even for reading.   I know some windows-based backup programs 
> don't have the problem so I'm hoping there's some way to avoid it in 
> cygwin.  I've looked at the cygwin mount options but don't see anything 
> obvious.  Is there a way around it?

Hello, Richard
You need to use VSS which stands for 'Volume Shadow copy Service' (or  'Volume Snapshot Service') on Windows. It is based on copy-on-write technology below the NTFS level and is used by Windows to make backups of the running system including of opened and locked files. (Also VSS utilizes a number of 'writers' that helps to make a consistent backup of opened database files for instance.) The shadow copy may be created by using different userspace tools:
* vshadow.exe (http://msdn.microsoft.com/en-us/library/bb530725(VS.85).aspx)
* vssadmin.exe (on the server OSes)
* wmic.exe
* by calling COM WMI objects from windows script host (http://support.microsoft.com/kb/188135) - VBA or JS scripts or from Windows PowerShell scripts.

The easiest way to access the created shadow snapshot:
 http://blogs.msdn.com/b/adioltean/archive/2008/02/28/a-simple-way-to-access-shadow-copies-in-vista.aspx
Then rsync can be used to copy files from the shadow snapshot after which the snapshot can be deleted.

I believe there are already working solutions and programs that can be found. For example these articles:
 http://users.softlab.ntua.gr/~ttsiod/win32backup.html
 http://blog.jay2k1.com/2011/08/13/how-to-create-rsync-like-hard-link-backups-with-vss-on-windows/

If you will find something satisfactory for you, please let me know.

--

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple