I have been noticing this error on all of the SharePoint Farm servers across all environments. I never saw this error before.
SQL database login for 'DBConfig' on instance 'DBServer' failed.
Additional error information from SQL Server is included below. Login failed for user 'Domain\machinename$'
Found a fix (link below) which asks you to execute Add-spshelladmin -username 'Domain\machinename$' but I wasn't sure if it is safe. When you execute this, you will see the 'Domain\machinename$' added to the WSS_ADMIN_WPG group on the server where you execute the command.