The original post: /r/datahoarder by /u/kingman1234 on 2024-08-17 10:35:45.

Background

I'm running a home server with a "file server" set up. Size of the target backup data is around 400 GB only (I know it is small. It contains Proxmox VM backups and my family's personal files on the file share.) The file share is on a ZFS mirror tool. I have already set up SystemD timers to regularly snapshot the datasets, back them up to a restic repository, and sync that repository to Backblaze B2 using rclone.

I'm now thinking of an additional on-site cold backup solution at my home. This on-site backup should be write once read many (WORM) to greatly minimize the risk of any pesky ransomware. I intend to do a manual backup every 6 months to several sets of WORM media. I have searched a lot in this subreddit and I've come up with the following solutions:

BD-R

I'm able to get a USB BD burner for like US$60-90, and Ritek 25GB BD-R for US$13/50 discs. I believe M-Discs is not necessary for my use case as if the discs last for 3 years they will be good enough.

Pros:

• Real write once media

Cons:

• The backup will need to be split into multiple discs. It will be a bit of hassle to change the discs to backup. Also it will be a bit of hassle to restore as all discs need to be copied to a hard drive big enough to hold the backup before performing the restore.
• It feels like it is a stagnant, obsolete technology with fewer and fewer companies producing BD-R now.
• From buyer's comment, it seems that around 1 in 50 discs will fail to burn or fail verification right after burning, which seems concerning to me.

Hard Disk

I'm thinking of getting an IODD ST400 enclosure (around US$100) for its write-protect functionality, and several 1TB 2.5 inch spinning hard drives (around $40 each) to rotate from.

Pros:

• The IODD ST400 enclosure can double as a bootable virtual ODD for testing/installing ISOs. (From my experience Ventoy may not be completely reliable)

Cons:

• Can't find any information on how well the write protection on the IODD drive works. Hopefully it isn't as bad as the write protect swicth of SD cards (which some readers outright ignore them)
• It also feels like the 2.5 inch spinning hard drives are slowly getting obsoleted (max capacity of drives seemed to be 2TB). I'm avoiding SSDs as they can lose their charge over time during storage. And I couldn't find any USB 3.5 inch HDD enclosures with the write protection functionality.

LTO tape

I know it is the "holy grail" of cold storage. I'm able to find a second hard HP Ultrium 3000 LTO-5 SAS drive for around US$100. Not sure if it is legit. Couple this with an LSI SAS 9300-8e HBA external SAS card, an SFF-8644 to SFF-8088 cable and a couple of 3TB LTO-5 tapes, and it seems to be a workable solution.

Pros:

• The holy grail as I've mentioned

Cons (or concerns):

• Unfamiliar technology: I still don't know if the above works. Hopefully someone more well versed in this topic can comment on this. Will the SAS drive works without extra driver on Linux?
• I also search local forums and I can see additional two concerns mentioned - noise of the drive and longevity of tape in an uncontrolled storage environment. Noise may not be a great concern as I'll be only doing it half a year. But I don't know if the LTO tapes can survive without 24x7 air conditioning (the room can get to around 30 deg Celcius/ 90 deg Fahrenheit and 80-90% RH without air conditioning)
• Overkill solution to have for a set of data only around 400GB in size?

Thoughts?