Obviously the access of HSS to the database did not succeed.

You should check if access permissions to the database is enabled for HSS.

Check the GRANTs on the database hss_db.

mysql -u root -p

show grants for 'hss'@'server.net1.test';

quit;

The result should be:

+-------------------------------------------------------------------------------------------------------------------+

| Grants for hss@server.net1.test                                                                                   |

+-------------------------------------------------------------------------------------------------------------------+

| GRANT USAGE ON *.* TO 'hss'@'server.net1.test' IDENTIFIED BY PASSWORD '*AC83FCF24B79020EF2C51D780CDFA559F25CC9BE' |

| GRANT SELECT, INSERT, UPDATE, DELETE ON `hss_db`.* TO 'hss'@'server.net1.test'                                    |

+-------------------------------------------------------------------------------------------------------------------+

BR Franz