Welcome!
Important information
-- Spectre and Meltdown vulnerabilities
-- Change in MX sources

News
-- MX Linux on social media: here
-- Mepis support still here

Current releases
-- MX-17.1 Final release info here
-- antiX-17 release info here

New users
-- Please read this first, and don't forget to add system and hardware information to posts!
-- Here are the Forum Rules

[SOLVED] 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

Message
Author
User avatar
fehlix
Forum Guide
Forum Guide
Posts: 1156
Joined: Wed Apr 11, 2018 5:09 pm

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#11 Post by fehlix » Thu Jul 26, 2018 8:34 pm

Brasero is known to produce bad DVD's. ( It's a long story...)
Better use xfburn which uses xorriso ( which also used by MX/antiX ISO maker ).
You will not find much complains about the later regarding quality ot the ISO/DVD's.

User avatar
MX-16_fan
Forum Regular
Forum Regular
Posts: 917
Joined: Mon Feb 13, 2017 12:09 pm

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#12 Post by MX-16_fan » Fri Jul 27, 2018 8:05 am

fehlix:
fehlix wrote:
Thu Jul 26, 2018 8:34 pm
Brasero is known to produce bad DVD's. ( It's a long story...) (...)
Thanks for the warning.

What's that story, in short?


Greetings, and have a nice weekend, Joe

User avatar
Mauser
Forum Regular
Forum Regular
Posts: 562
Joined: Mon Jun 27, 2016 7:32 pm

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#13 Post by Mauser » Fri Jul 27, 2018 8:19 am

fehlix wrote:
Thu Jul 26, 2018 8:34 pm
Brasero is known to produce bad DVD's. ( It's a long story...)
Better use xfburn which uses xorriso ( which also used by MX/antiX ISO maker ).
You will not find much complains about the later regarding quality ot the ISO/DVD's.
That's funny because I have sometimes experience bad DVD burns using xfburn.

User avatar
Mauser
Forum Regular
Forum Regular
Posts: 562
Joined: Mon Jun 27, 2016 7:32 pm

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#14 Post by Mauser » Fri Jul 27, 2018 8:23 am

MX-16_fan I suggest selecting the slowest burn speed setting when burning DVDs for the best quality results because at higher speeds have the higher possibility for errors.

User avatar
ChrisUK
Forum Regular
Forum Regular
Posts: 144
Joined: Tue Dec 12, 2017 1:04 pm

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#15 Post by ChrisUK » Fri Jul 27, 2018 8:49 am

Concerning Brasero and Xfburn:

The developer of one of the CD/DVD back-ends/libraries (libburn) was in another forum that I'm a member of - it was a few years ago, but he explained the difference between Brasero and Xfburn. Obviously, (due to my age and misuse of drugs in my youth ;) ) I remember very little of what he said - I do remember that it depends on your hardware. Older hardware works fine with Brasero - newer can work better with Xfburn.

I use Brasero daily, can't remember the last time it made a coaster... hardware is 7+ years old.
Chris

MX 17 - Manjaro - LMDE

User avatar
MX-16_fan
Forum Regular
Forum Regular
Posts: 917
Joined: Mon Feb 13, 2017 12:09 pm

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#16 Post by MX-16_fan » Fri Jul 27, 2018 10:06 am

@Mauser:
Mauser wrote:
Fri Jul 27, 2018 8:23 am
MX-16_fan I suggest selecting the slowest burn speed setting when burning DVDs for the best quality results because at higher speeds have the higher possibility for errors.
Already did so. Burned at 1x speed. Greetings, Joe

User avatar
Mauser
Forum Regular
Forum Regular
Posts: 562
Joined: Mon Jun 27, 2016 7:32 pm

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#17 Post by Mauser » Fri Jul 27, 2018 1:48 pm

MX-16_fan wrote:
Fri Jul 27, 2018 10:06 am
@Mauser:
Mauser wrote:
Fri Jul 27, 2018 8:23 am
MX-16_fan I suggest selecting the slowest burn speed setting when burning DVDs for the best quality results because at higher speeds have the higher possibility for errors.
Already did so. Burned at 1x speed. Greetings, Joe
Thanks. O.K. Cool.

scdbackup
Forum Novice
Forum  Novice
Posts: 12
Joined: Tue Jul 28, 2015 5:59 am

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#18 Post by scdbackup » Sat Jul 28, 2018 2:31 am

Hi,

fehlix wrote:
> Better use xfburn which uses xorriso

It uses libburn and libisofs which also serve underneath xorriso.
Brasero has plugins for using those libraries.

Mauser wrote:
> That's funny because I have sometimes experience bad DVD burns using xfburn.

All burn backends use the same set of SCSI/MMC commands to burn the medium.
So in most cases it is about the relation of drive and medium, not about
the burn program. (In rare cases of dying drive, some of the possible
variations of the burn procedure can trigger failure.)

HrisUK wrote:
> The developer of one of the CD/DVD back-ends/libraries (libburn) [...]
> explained the difference between Brasero and Xfburn.

That's me. :)

> Older hardware works fine with Brasero - newer can work better with Xfburn.

Not really. The GUI programs can choose between "write types" like
"Disk-at-once" and "Incremental". They can choose speed (which i deem
not as significant for success as others do), and they can spoil the
transfer of data from ISO 9660 producer to burn backend (Brasero did
for a while back in 2010).

The main work is done by backends: cdrecord, growisofs, or libburn.
They have more opportunities to do it wrong.

----------------------------------------------------------------------

Now for the original question:

DVD have several layers of error detection and correction bits. If the
medium is good directly after burning, then it needs a substantial
physical accident to spoil it. (Or maybe the infamous CD eating fungus.)

So the first and foremost long term preparation is to checkread the
burned DVD and to watch for unexpected slowdowns during reading or
even for comparison errors.
Most burn programs can do this at the end of a burn run.

But they do not necessarily store own checksum information so that one
can verify the DVD years later. They also do not store checksum information
about the individual data files on the DVD.
So for verification before using or restoring the DVD we would depend
on the hardware error detection which would report I/O errors in case of
failure.

It is rare but not impossible that a DVD returns bad data but causes no
I/O error. This makes desirable own checksums which are independent of
the hardware features. You should choose a storage format which is able
to store and retrieve such checksums.

For ISO 9660 filesystems, i use xorriso command -for_backup to record MD5
sums of the total filesystem and for the particular data files. E.g. to
copy disk the files under directory "$HOME"/files_for_dvd to the root
directory of the DVD:

Code: Select all

xorriso -for_backup -outdev /dev/sr0 -map "$HOME"/files_for_dvd /
Afterwards (and at any time later) i check for correct readability by:

Code: Select all

xorriso -for_backup -indev /dev/sr0 -check_media --
(Note that the arguments to xorriso are commands similar to shell commands.
Their sequence matters: First enable MD5 processing by -for_backup, then
load the ISO metadata by -indev, then start a checkread run by -check_media.
The list of -check_media parameters ends by argument "--".)

In order to check particular data files or trees, i use command -check_md5_r:

Code: Select all

xorriso -for_backup -indev /dev/sr0 -check_md5_r sorry /the_pictures --
All files under directory "/the_pictures" will be checked. In case of
mismatch, an error message of severity "SORRY" wil be emitted.


Have a nice day :)

Thomas

User avatar
ChrisUK
Forum Regular
Forum Regular
Posts: 144
Joined: Tue Dec 12, 2017 1:04 pm

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#19 Post by ChrisUK » Sat Jul 28, 2018 2:40 am

I was wondering if you'd notice this thread, Thomas... thanks for the detailed info, much more accurate than my failing memory ;)
Chris

MX 17 - Manjaro - LMDE

scdbackup
Forum Novice
Forum  Novice
Posts: 12
Joined: Tue Jul 28, 2015 5:59 am

Re: 7z, DAR, tar, tar.gz: Which is safest for "long-term" storage of data on an optical disk?

#20 Post by scdbackup » Sat Jul 28, 2018 2:55 am

Hi,

ChrisUK wrote:
> I was wondering if you'd notice this thread, Thomas

You can hardly say "xorriso" in the web without Google taking notice.
I just have to ask it for the "Past 24 hours" matches of search text "xorriso".

Have a nice day :)

Thomas

Post Reply

Return to “Software / Configuration”