To be clear (since this is in the lounge) I'm asking about backup in general, not specific to Joplin. My Joplin backup is made to the same drive as my regular install so it needs to be backed up somewhere else, and I'm having a hard time finding solutions.
Specifically I'm interested in backing up to a physical drive.
I used to use an inexpensive paid software, but they changed to a yearly subscription. I wouldn't mind having to pay for one time with a year of updates. But yearly just isn't feasible.
What I really liked about that software was that it worked by synchronizing (one direction) so the backup was completely accessible (no restore needed). It even dumped the old/deleted stuff into a temporary folder so you could look back at those files if needed.
And for the sake of discussion I'm happy to hear about all things backup.
I use Karen's Power Tools Replicator (free) for basic backup, and SecondCopy ($30) for more complex backup. SecondCopy though is also pretty basic - just copies so you have a 1 to 1 version, not compressed etc, you can refine your copying to a greater degree.
i've been using the free version or AOMEI Backupper (disk images and individual directory backups) for a few years. it's worked pretty flawlessly for me so far and the restores have worked every time.
I use borg, as it's relatively easy to use and it's encrypted. You can also store multiple incremental backup sets within the same archive, and they provide a FUSE driver to easily explore a backup from a regular file browser.
So far I never had any issue with it so it seems to be reliable.
Robocopy comes with Windows and has options for just about anything you'd want to do. I've been using it to back up Windows directories for decades. Next, if you want to backup the system partition, you typically need to do that with Windows offline, i.e. not booted. For that, I use CloneZilla, which is free, running off a bootable USB stick. I back everything up to a QNAP NAS. But my backups are all just storing directories and files, so any attached storage will do. Before I purchased a NAS, I used an old PC with a shared directory for backups.
If you also run Linux, CloneZilla can backup Linux partitions. If you want to back up files or directories while Linux is running, rsync works fine for that.
I prefer this way of backing up because you don't need any extra software to access the backup files.
However, if you need to back up large files such as databases, this method takes up a lot of space.
I use Duplicati, which is encrypted as well, but not particularly easy to use, I must admit. I'm fond of it nevertheless, and I want to support its future development.
Very true! This is partially my fault since I opened up the conversation to other types of software in the text of my OP. I did this out of desperation since I was afraid that no FOSS solution existed.
It's really strange to me that there are not more FOSS options since backing up things should be such a common task.
There are lots of good FOSS options but usually they are not that user friendly since they don't have any GUI. On macOS probably the best option is Time Machine for users who don't want or don't know how to configure command line tools, and I think Windows also has some built-in solution (but maybe not as good)?
Yes, I think you are exactly right. Even though I do use command lines now when I have to, I know that unless I have a GUI, I'm unlikely to do it as often as I should. Even then I don't back up as much as I should.
I suppose I could come up with a command that did what I needed. But then if I ever had to do something different it would be a deep dive back into the documentation.
I use backuppc on a linux server to back up windows and linux systems.
If you are choosing a new backup solution you really should prioritize a few features-
read only access
Ransomware is very real. A backup that is writable could be corrupted by malware. A remote system that pulls data for backups can be out of the reach of ransomware.
automated backups
Backups can be done daily or more often if there is easy automated execution. A recent backup can help with both major failures and simple user errors.
archive to remote locations
If you have a backup in a remote location it covers that flood/fire/burglary nightmare. An encrypted backup can be stored in a cloud service without having to trust its security.