Best format for backing up data in Blu Ray

2

We are in the process of backing up our hard drives to Blu Rays. I am creating tar.gz files and burning them to Blu Ray.

Is it possible to use a simple (preferably Python-based) solution for creating images of those tar.gz files, of a predetermined size (to fit in the Blu Ray), and simply burn this images to the disc?

Do you have any other approach for creating physical back-up of your hard drives?

Escualo

Posted 2010-01-25T23:30:26.837

Reputation: 245

3You're not worried about the dyes degrading? I've got CD-Rs from ~5 years ago stored under optimal conditions that are unreadable. Tape is pretty standard, and the cost per GiB is slightly less than that of hard drives (and significantly less than Blu Ray. Using python you could sort all of your tar.gz files by size and then use some naïve packing taking the biggest then smallest and then use mkisofs to make your isos. – Tyler – 2010-01-25T23:56:39.287

1Tyler is right, optical media is notorious for degrading over time (especially if the integrity of the coating is compromised via scratch or similar that will allow oxidation to occur in the aluminum). If you are looking for long-term viability tape is the way to go. If you only are planning on having these as a failsafe, why not just dump the data onto external hard drives? The cost per GB will be much cheaper, and it will take significantly less time to create the backups. – TJ L – 2011-01-13T16:20:25.813

Answers

0

Tar really is the best format for archives. Every system you want to recover on will have it.

I use the tarfile Python module to make my tar.gz files and an index file with hashes. I have my program create a new tarball when the current one reaches a certain size. You could then run mkisofs and cdrecord with popen to create the ISOs and write them to disk.

I use tarsum.py to verify the hashes during recovery.

Jeff Strunk

Posted 2010-01-25T23:30:26.837

Reputation: 331

Do you really compress your data before backup? I'm not sure that's such a great idea in case of read failures. – einpoklum – 2017-01-05T23:25:00.830

I wrote multiple copies of each archive disk because I expect disk failures. I also needed to store the copies at different sites. – Jeff Strunk – 2017-01-10T13:20:33.827