I have several Drupal sites on an AWS Lightsail instance, and would like to push weekly backups to S3. The backup process seems to work, and successfully pushes files to S3 (I've done this on other server setups).
However I'm noticing when the Backup routine runs, it doesn't dump the MyQL database for all of the sites - only one. That is, there are 3 sites on the server, each with its own MySQL DB, but only one of them is getting dumped.
I've harmonized the permissions for the three db users - no joy.
Any ideas where to turn next would be appreciated.
UPDATE - same thing happens when I'm backing up to a local directory. Also I've tried this on another server with different domains, with similar results.
Any help appreciated.