Hi all, recently, my Raspberry Zero, that used to do backups by dirvish, took his hat......
As I don’t have a replacement to hand, apart from a few OpenWRT routers that sit around unused at night, I thought it might be a good idea to use them.
I don’t want a large, complex backup solution where you need the installed backup software to access the backup files. Instead, I like the concept of backups using hard links (e.g. Dirvish or rsnapshot). The appeal of these is that they offer a streamlined solution and you can access the files using standard tools.
Bearing these requirements in mind, you arrive at a backup solution that either does not use encryption for your backups (in which case you don't ever need to encrypt any file) or uses encryption at a lower level.
I would like to set up something like dirvish or rsnapshot. So, as a first step, I have set up a script to mount and unmount LUKS-encrypted partitions (e.g. ext4).
It is at a mature stage of development and is available under
https://github.com/thiloreski/crypto-manage
Any comments are welcome
Bestet
Thilo
(I wrote this post myself , but the script and the documentation is all done with extensive help of AI.)
The typical plastic router does not make a good NAS. Yes, ARMv8 has improved the situation significantly, but there are still many bottlenecks left - even more so when it comes to refreshing delta backups. Network throughput for hosted files (cifs, sshd, nfs, etc.) is limited and CPU intensive, RAM sizes are always on the low side, the CPU will be taxed massively (checksum verification for delta backups), IOPS go to hell.
It's possible, if used conservatively and if you don't expect frequent delta syncs.
…security implications and attack surface would be another topic.
'Big' HDDs don't make sense (USB case and additional power brick needed, so your power consumption is not great).
'Fast' SSDs don't make sense either, as IOPs and max throughput are substandard.
jee, all your arguments are valid , off course, but I have the feeling that the EA7500v1 (currently in charge for this task) performs better that the raspberry zero 1.1 which I had for backups earlier. Apparently: 1) Yes, a 4T disk in an seperate case with its own power supply, 2) there is not so much sync, just at night an "rsync -link-dest=latest_backup sorce target" is running. 3) the changes which have to be downloaded are limited, there are only 2 persons in this home office and whatever these two change durng the day is downloaded in less than one hour....
For a small nightly home backup job this sounds reasonable, as long as you treat it as a convenience box and not the only copy. I’d keep the LUKS key/passphrase off the router if possible, or at least make manual unlock the default, so a stolen router plus disk is not enough. Also do a real restore test from the encrypted disk before trusting it; rsync/link-dest setups can look fine until permissions, ownership or mount paths are slightly wrong.
, but the script and the documentation is all done with extensive help of AI.)