To backup everything:
- In the steps below, ensure calibre is not running.
- Use a program like FreeFileSync to mirror your library to where you want it saved. Do not use two-way syncing.
If you have enough space in a cloud drive, mirror the library to there so you have an off-site backup. NG: There have been incidents where backups mirrored to Google Drive aren't usable because of Drive's versioning scheme. YMMV. DO NOT use a cloud drive for your library.
- Plugins and many calibre settings are stored in the calibre configuration folder. Again, use a program like FreeFileSync to backup this folder to where you want it saved. You can find where the configuration folder is stored using calibre: go to Preferences / Miscellaneous / Open calibre configuration folder. Note the path. It is usually in a home folder. For example, on Windows it is usually in \Users\*you*\AppData\Roaming\calibre.
Again, mirror the configuration folder to a cloud drive if you have cloud space.
- You can keep a history of the configuration folder contents using the Backup configuration folder(s) calibre plugin. Mirror the folder where you save the backups to a cloud drive if you have space and wish offsite backup for the history.
Restoring from these backups is straight forward; copy the mirrored backups back to their source.
Again,
DO NOT use a cloud drive to store an active library or configuration folder.