Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, and inform them of the time the error occurred, and anything you might have done that may have caused the error.

MongoDB::SelectionError: No readable server available for matching read preference primary. MongoDB server status:
    Topology type: Single; Member status:
     localhost:27017 (type: Unknown, error: MongoDB::NetworkError: Could not connect to 'localhost:27017': IO::Socket::INET: connect: Connection refused )

Apache/2.4.6 (Red Hat Enterprise Linux) Embperl/2.5.0 OpenSSL/1.0.2k-fips mod_perl/2.0.11 Perl/v5.16.3 [Sun May 16 19:44:12 2021]