How to backup large sets of data to a series of Bluray discs reliably?

Question

I have several hundred gigabytes of data to backup and would like to back them up to 25 GB Blu-ray discs.

So far I've attempted to use Toast Titanium to accomplish this, but after burning about 5 discs, I end up hitting a wall where the drive just seems to time out. Obviously this is costly problem as I'm losing those 4-6 discs each time and I've already burned up about $30 worth of discs trying this.

It seems to me that there should be a better option, perhaps even somehow manually doing this. The problem is space optimization; you end up with a lot of blank space on discs if you manually handle things like this.

I've thought that perhaps there may be some software out there that would analyze the storage requirements on a set of folders and then build a series of folders named something like "Disc 1", "Disc 2", etc. and then populate these with symlinks that would then facilitate being able to perhaps burn these to a disc one by one manually and thus minimize disc loss since programs like Toast simply throw your progress away in the event of a failure.

While I'm on macOS, I could share these volumes to Windows or Linux as needed if there's no workable solution on macOS for such a scenario.

Any ideas of solutions that facilitate this kind of disc by disc burn flexibility?

Answer 1

I've found that macOS just doesn't treat optical drives as well as it should. After extensive testing on two different optical drives, I've found that disc burning fails about 25% of the time and reaches points where a series of backups with something like Toast that spans many discs will hit a point where it just fails permanently and you have to give up, thus losing your first discs effectively. This happens when you go past 5 or so discs. Toast may work okay for a couple discs, but I wouldn't trust it beyond this.

Upon moving the same hardware to a Windows machine and using Nero, I've found near 100% success rates after going through about 20 Blu-ray discs. Compared to macOS and Toast this is phenomenally better performance. Not a single coaster.

I even tried a direct connect to a Windows 10 virtual machine via Parallels of the USB Blu-ray burner and had the exact same problem that I experienced in Toast, but with Nero. This was strong evidence that macOS is just having trouble in some fashion that is not easily traceable.

I suspect that Apple has more or less divorced themselves from optical storage technology since they've been pushing so hard away from it for the last several years and that we're better off steering clear of using it on macOS except for reading (which of course isn't as serious of a problem with pure read sans the risk of making coasters).

Answer 2

Assuming the root cause of the issue is potentially the optical drive, then I see two choices.

1. Replace the drive. This is probably only worth it if you are storing to true archival optical media, 100-year+ lifespan.

2. Store it to two regular hard drives, kept in two places.
   The downside of hard drives is the data needs to be refreshed every couple of years, or the 'magnetism gets tired', the upside is they're cheap.