mod_backup
mod_backup serves two different purposes: it makes a nightly backup of your files and database, and can also backup/restore individual resource items.
Daily backup of database and files
Losing data is bad for business. This applies to your customers as well if you are building sites for them. It is critical to keep backups of any Zotonic sites you develop.
After enabling mod_backup, it will make a backup of the site’s data every night at 3 AM. It keeps the last 7 daily copies of the data, so you have always a backup to roll back to.
The backups are stored under backup in the files directory of
your site. Check in the admin under System > Status to see where the
site files directory is located.
The site’s media files are stored as a .tar.gz file, while the
database is stored as an uncrompressed .sql file.
If mod_filestore is enabled then the media files are not backed up, as it is assumed that the files are already backed up on the cloud filestore. The data backups are uploaded to the cloud filestore, so they are also backed up.
If mod_filestore is not enabled then we advise to add a cron script to the server for copying the data to remote storage.
Per-resource revision log
If a resource is updated or deleted then a copy of the resource data is saved to a revision log.
Using the revision log a resource can be rolled back to an older revision or, when deleted, recovered.
Revisions older than 18 months are daily pruned. This can be changed by
setting the configuration mod_backup.revision_retention_months to another
number of months.
Currently edges (connections) and medium files are not kept in the revision log.