All websites are not available.
Apache configuration is inconsistent.
plesk sbin httpdmng --reconfigure-allhas been executed or configuration files were recreated using the link in error message like the following:
PLESK_ERROR: Please resolve the issues and click here to generate broken configuration files once again or here to generate all configuration files
All sites files are missing from
# ls -l /etc/httpd/conf/plesk.conf.d/vhosts
The issue has been registered as a bug and will be fixed in future Plesk versions: PPPM-10984.
Best practices to avoid this from happening:
It is first recommended to reconfigure a single website to make sure the issue is resolved:
# plesk repair web example.com
Then, the command can be executed to repair configuration files for all domains:
# plesk repair web -domains-only