[Digikam-users] Backup options?? probably off topic

[Simon Cropper]

On 17/07/13 12:34, Fabio wrote:
> Hi All,
>
> I am not sure this is the proper channel but I could not find any other
> digiKam forum
>
> Digikam strong area is organization and exporting to other places. Now,
> I am looking for backup options. The easiest way is just to copy all
> files from my local album to 2 external drives. Problem is Once I made
> the first copy, how can I keep updating only photos I have been
> changing. I am going back and editing old photos but no tin a very
> organized way.
>
> Does digiKam provide backup options like incremental backup (copy only
> what is new or changed)?
>
>
> Thanks!
> _______________________________________________
> Digikam-users mailing list
> Digikam-users at kde.org
> https://mail.kde.org/mailman/listinfo/digikam-users

Fabio,

Very large image collections, as created by digiKam, creates a unique 
scenario and so I think it is not that "off topic" to ask the question 
on this forum.

The way that digiKam works is to catalog all the images and associated 
metadata in a database; usually stored in the top most directory of your 
albums. Although uncommon this lists has reports of people trying to 
recover their tags and metadata from corrupted databases as they have 
not ensured that this information is stored elsewhere.

DigiKam provides the ability to save metadata to associated XMP files 
and to store metadata tags, copyright information and captions inside 
the files (JPGs only). I would recommend you do this -- it generally 
does not have a significant overhead. This option allows you, in the 
circumstance where you database becomes corrupt to recreate your 
database based on the information stored in these files.

The next issue is conventional backup. Albums are just directories so 
are easily backed up using any of the packages mentioned (rsync, Unison, 
BackupPC, grsync, Timemachine). Ideally you should have all your 
electronic files backup, so asking the question is a little bit of a 
concern :).

To help...
1. Solutions are either GUI-based or Script-based. GUI-based solutions 
are good to get you going. Script-based solutions require some level of 
"programming" so you will need to take the time to read the manual, 
construct a script and test it.
2. Ensure your backup creates a mirror of your original files. That way 
if your primary disk dies you can just start using one of your backups. 
Some incremental software bundles zip collections or compress the files 
and you need to uncompress and reconstruct your original collection if 
you wish to recover your files. This can be a nightmare!
3. You need to decide if you want some level of versioning. If you 
mirror your collection and corrupt a file unknowingly you can have the 
corrupt file copied to you backup resulting in the loss of the original 
good file. In general, due to size of most people's collections people 
don't create versions. If you use scripts however it is pretty easy to 
make copies of your collection for each month. Hard disk space is cheap 
and a script that copies originals to a safe place for a couple of 
months are not that hard to make.

All that said, I will tell you what I use...

On Windows I use RoboCopy. It is a command line program that can have 
instructions kept in a batch file. The program is free from Microsoft. 
The syntax is easy... for example...

robocopy c:\images \\backup\images /mir /ns /R:2 /NP /NDL /Purge /tee

I have tried a range of packages on Windows but the only software I 
liked was AllwaySync -- a good application for small collections.

http://allwaysync.com/

*I now primarily use Linux*. All my backup is automated using rsync. 
This package is very much the same as RoboCopy. You insert a series of 
commands in a script file and run the script. My script creates a mirror 
of my entire network, including my image collection. Again the syntax is 
easy... another example...

rsync -rltvz --stats --delete --ignore-errors /home/simon /media/backup

In some situations, on Linux, where I want short term backup solutions I 
use FreeFileSync. It is easy to use and to create simple backup options.

http://freefilesync.sourceforge.net/

Remember...
A. Backing up large collections over a network can take forever. Make 
your initial backup by connecting your backup drive to your computer via 
USB or actually plugging it in (internally). Then move it to a remote 
location once the backups are completed. Incremental backups should not 
be too much of a load on a normal network.
B. All backups require you to be able to "see" the backups. If you 
temporarily connect a USB drive this is not a problem for either Linux 
or Windows. When you work with remote computers however it is usually 
easier to mount the drives. On Windows this is done by mounting a 
directory on your backup drive to a letter. This allows you to insert 
your name and password once and have that mounted drive open whenever it 
is available. On Linux, this is a little trickier. Mounting is done 
using the mount command and requires a little effort and testing. The 
exact syntax depends entirely on the distro (e.g. Ubuntu, RedHat), hard 
disk format (e.g. ext3, ext4, NTFS, FAT32) and connection strategy (e.g. 
NFS, CIFS).

-- 
Cheers Simon

    Simon Cropper - Open Content Creator

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