Otherwise, I am at a complete loss here at the moment. If so, maybe someone else has the same problem and a fix or workaround. I have read that similar problems have occurred with ca certificates going out of date suddenly, and perhaps that is it. This is uniquely an issue with restic to backblaze. So, restic locally is working fine to the usb drive as usual. The restic-2-backblaze is just a copy of the usb local backup. That is working fine and verifies with check fine afterwords. I should also point out that I use similar scripts to backup to a local usb drive first. So, I know it is something going on with restic alone, not connecting to backblaze at the moment. Indeed, I also run a daily home directory sync using this b2 program with the sync option, and it is still working fine. I can also run a separate backblaze b2 script (b2 program compiled from source for linux provided by backblaze) it works with the same keys. It appears to login to backblaze, because if I change the backblaze key ID to something different, it gives me a message. I have the verbose level at the max of 3, but still nothing comes out to the screen. I have narrowed it down to the restic command itself. Now, I can verify that none of my backup scripts are working at all. Now, all of a sudden, in the middle of a backup last night (about 4am, 8/23/22), it stopped working. It has been working flawlessly now for several weeks, and really works well much better than trying to backup to dropbox or google-drive as I was doing earlier when I first started using restic. Each filesystem backup is stored as a separate folder underneath a backblaze bucket.

I am setup to backup by filesystems at the rate of two per night for a total of 14 backups over the week. I am also using backblaze b2 to backup and store to the cloud about 1 TB of data from this system. I have a linux/debian/bullseye/11.4 system with restic 0.13.1 compiled with go1.18 on linux/amd64 installed.

Backblaze linux support