Domains are deactivated automatically by Plesk during the backup
process and it appears that more often than not Plesk does not
reactivate the domains when the backups are finished resulting in
clients finding their domains offline and inaccessible.
If you are finding your domain is offline for any reason please contact
support to have it reactivated, this bug is currently out of our
control, the only alternative we can recommend is to use the code below
which will allow you to safely and reliably backup your critical
databases.
Unfortunately, this option does not backup your domain data, files etc.
For an easy way to backup your databases daily and safely, please see
the following CRON script below: