Keith C. Perry on 31 Aug 2014 07:17:02 -0700

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Re: [PLUG] Image-based partial backup?

Lzo is an opportunistic compression so on the compression side of things its faster and also tends to be better in network situations.  I switched from gzip to lzo because the solution I built was increasingly streaming to remote storage devices and as data sets got bigger, disk got cheaper so it made sense.  Run times shrank at a higher percentage than the space grew.  If your data is "moderately" compressible I would definitely try out ntfsclone with gzip to see how it does for you.  Playing with the gzip compression levels might help you tune the data flow so you can get the right balance of run time and storage utilization.   Something like...

ntfsclone --rescue -so - /dev/sda2 | gzip - > /media/backup/data_vol.clz

...will get it done.  Obviously in this example, "/dev/sda2" is your unmounted windows volume and "/media/backup/data_vol.clz" is the storage file.

33% @ 10 hours is definitely nowhere near what I've seen with the 2008 Server backup system.  Pretty useless.

If you are trying to avoid the reinstall headache, I would still go with an image.  Using dd and gzip has the benefit of including the boot information along with data in one file.  It wouldn't be as small as the file above and it would take longer to run but you also don't have create a separate copy of the boot sectors (which in my case, I would be using dd for anyway).

For what its worth, the way I address the run time issue is make sure the windows box system partition is just the system.  Lets say you have 1 Tb drive.  That would take a long time especially with something like dd.  However, if its partitioned- sda1 is a 100Gb system and sda2 is 900Gb of data then you only have to image the boot sectors + sda1.  Such an image would give you a bootable system and a D partition ready to be formatted.  You can resize the windows partition before restoring data to it as well.  Now that the data is on a separate partition you can use ntfsclone or any file based backup in linux- rsync, tar, etc..  That's still only two files so this combination is very portable, space efficient and eliminates the rebuild headache.

Things may not be organized that way for you now but it might be worth the effort for future gains.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 
Keith C. Perry, MS E.E. 
Owner, DAO Technologies LLC 
(O) +1.215.525.4165 x2033 
(M) +1.215.432.5167 

----- Original Message -----
From: "Rich Freeman" <>
To: "Philadelphia Linux User's Group Discussion List" <>
Sent: Sunday, August 31, 2014 7:08:24 AM
Subject: Re: [PLUG] Image-based partial backup?

On Sat, Aug 30, 2014 at 9:59 AM, Keith C. Perry
<> wrote:

> How compressible is that 300Gb though?  I generally use lzo
> compression but if times isn't a factor you might be some surprisingly
> good results with gzip or bzip2.

Clonezilla supports compression.  I've actually found gzip to be the
best option, because clonezilla supports multi-threaded compression.
I believe the main difference between gzip and lzo is that lzo
decompresses faster, and that isn't a major consideration for a backup

My data should be moderately compressible.

> I don't think that facility is in Windows 7.  I wish it was because
> 2008 Server is almost as easy to move around as my Linux xfs volumes.

Well, I'm running a Win7 backup now to see how it works.  It has been
running for about 10 hours and is 33% complete.  That is WAY slower than
clonezilla.  It looks like it compresses data locally into zip files
before sending it over the network, which explains why it is so slow.
The thing is the zip files are only 200MB each, so it could easily just
buffer those in RAM assuming it needs to buffer them at all.  Really
lousy implementation, but it runs online so maybe I'll just tolerate
that or figure out some way to point that at a RAM disk or something.

I'd really prefer something FOSS though.  I just feel like I'd have more
options if something goes wrong.  Then again, for the Windows box there
is actually nothing critical data-wise on it in the first place which
isn't already backed up in other ways.  So, this is mostly about saving
me time re-installing everything if the disk crashes.

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