When attempting to upgrade CABI JasperServer 6.3 to 7.1.1, it fails with a "Cannot connect to the database server" message:
CABI JasperServer 6.x
Red Hat Linux 7.x, 8.x
Stopped the JasperServer and then had to manually stop the Postgres DB using the 'fast' option:
This immediately stops the Postgres DB processes by cutting any hung client connections.
Then restart the Postgres DB:
After this, the GUI install proceeds as normal: