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Re: Some help with dd backing up into an iso




On 03/07/2017 07:53 PM, GiaThnYgeia wrote:
Once you install a system like debian, does the information
in the hidden part of the disk ever change, of can I just copy the file
system partition as a backup and replace it if it breaks?

AFAIK when using MBR partitioning, the partition table (blocks 0-62) does not change if the partitions are not changed (start sector, size, type, flags, etc.).


OK, let's say swap is sdb1 and the filesystem is sdb2 (for this example
there is no other partition). There are about 2mb in the beggining of
the sdb then 2 partitions.  This is an actual working installation not a
live system.  With the exception of having to reinstall sound drivers I
got it working on 2 different but similar systems.  I was surprised it
did, but it does.  This may help me from having to maintain two separate
but parallel systems and just have one portable one and just use the hd
for just data files of work that I do.

I discovered that I can copy a Wheezy system drive image from an HDD/SSD to a USB flash drive, and the USB flash drive will then boot and run in several of my computers. I have not tried it with Jesse yet, but expect it will work.


Many of the examples I found were specific to partitions and not a whole
bootable disk.  Unless one studies filesystems it is hard to understand
why this 9660 is important.  What I understood is its limitation to long
and complex filenames.  So if I was to back up something with huge
filenames I suspect it may run into problems of altering them and not
being able to restore them correctly.  Have I made stew out of what I read?

If you want to burn files and directories to optical disc (I call this "archiving"), I suggest you start by using a simple GUI tool such as Xfburn.


My specific question with this is how often in a debian system do things
in the boot sector change, if ever.  I can't believe that if you have a
Debian2 and you change the source to jessie the bootloader stays the
same of it is the same with entering a fresh install of 8.7.1

The way to find out if the partition table changes between Debian releases would be to install a release of Debian, take an image of the first 2048 sectors of the system drive, hex dump it, install another release of Debian, take an image of the first 2048 sectors, hex dump that, and then run 'diff' on the two hex dumps.


... guitarist that
only cares about backing up his composition, recordings, midi files into
a stick and transport it to the studio.  If the studio only uses some
commercial expensive apple stuff it helps  having a file-system with you
to edit the files while on the run.

Having working copies of files on multiple disks is a double-edged sword. It works best if you only read the files. If and when you modify a file, now you have to figure out how to synchronize it to all the other disks. The risk is that you'll edit a given file in two or more places, and then have to solve the three way merge problem:

https://en.wikipedia.org/wiki/Merge_%28version_control%29#Three-way_merge


A version control system is very useful for keeping things straight, and warning you when you have a problem. I use CVS. The repository is stored on my file server. I can check out, update, and commit files on whatever computer and disk I want. The trick is to always update before you work on files, and always commit when you are done.


David