While backups are more of a security than privacy topic, i suggest to add the topic of backups to the knowledge base as well as recommendations for backup tools.
My reasoning for this suggestion is:
People who are new often don’t differentiate between privacy and security and subsequently come her for both. They might be prompted to think topics where privacy and security intersect is all they need to know and therefor won’t implement a backup strategy.
Although backups fall under the topic of security, there still can be privacy considerations, think of the questions “Should I use cloud storage as backup target?” or “Do commercial backup solutions phone home?” for example .
I also think it’s important because many of the more private options of things people want to do require some degree of self-hosting. If folks choose that option, they should know that backups are important to maintain the same level of confidence in the persistence of their data as they had on mainstream services like Google Drive.
I do think we need to discuss where the back up is going to be? Ie local, and cloud. The reason for this is because it’s not feasible to backup a lot of data to the cloud if your internet connection isn’t particularly fast.
I think if we discuss cloud products we must only recommend solutions which use E2EE and have been audited.
At the moment I personally use syncthing to my server and then do ZFS snapshots from there. Most people probably don’t have a NAS with ZFS so we should include some options that aren’t dependent on a RAID array like that.
I’m quite fond of rsync, because I think it can be an issue if your important data is locked up in some proprietary image format.
I used to use Duplicati, but had issue with backing up to Nextcloud server (webdav). It worked great for local (network) backup though. So I switched to Kopia, and it is great piece of software.