Can't connect to database when deploy

Hi there.
I currently try to deploy my app.
I run with default parameters for the database (HSQLDB with JDBC datasource in app).
When i deploy on other server, the app can’t connect to the database.

Here is the stackTrace:

=============================================================================================================
Some environment checks failed on core module:
Exception occurred while connecting to data store _MAIN_
        java.sql.SQLTransientConnectionException: java.net.ConnectException: Connection refused (Connection refused)
=============================================================================================================
15:52:54.218 INFO  c.h.c.c.s.p.PersistenceConfigProcessor  - Creating file /home/thomas/server/deploy/app_home/app-co                                                                                                                        re/work/persistence.xml
15:53:02.291 INFO  com.zaxxer.hikari.HikariDataSource      - Connection Pool-Main - Starting...
15:53:02.362 ERROR com.zaxxer.hikari.pool.HikariPool       - Connection Pool-Main - Exception during pool initializat                                                                                                                        ion.
java.sql.SQLTransientConnectionException: java.net.ConnectException: Connection refused (Connection refused)
        at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source) ~[hsqldb-2.4.1.jar:2.4.1]
        at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source) ~[hsqldb-2.4.1.jar:2.4.1]
        at org.hsqldb.jdbc.JDBCConnection.<init>(Unknown Source) ~[hsqldb-2.4.1.jar:2.4.1]
        at org.hsqldb.jdbc.JDBCDriver$1.run(Unknown Source) ~[hsqldb-2.4.1.jar:2.4.1]
Caused by: org.hsqldb.HsqlException: java.net.ConnectException: Connection refused (Connection refused)
        at org.hsqldb.ClientConnection.openConnection(Unknown Source) ~[hsqldb-2.4.1.jar:2.4.1]
        at org.hsqldb.ClientConnection.initConnection(Unknown Source) ~[hsqldb-2.4.1.jar:2.4.1]
        at org.hsqldb.ClientConnection.<init>(Unknown Source) ~[hsqldb-2.4.1.jar:2.4.1]
        ... 2 common frames omitted
Caused by: java.net.ConnectException: Connection refused (Connection refused)
        at java.base/java.net.PlainSocketImpl.socketConnect(Native Method) ~[na:na]
        at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:399) ~[na:na]
        at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:242) ~[na:na]
        at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:224) ~[na:na]
        at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:403) ~[na:na]
        at java.base/java.net.Socket.connect(Socket.java:609) ~[na:na]
        at java.base/java.net.Socket.connect(Socket.java:558) ~[na:na]
        at java.base/java.net.Socket.<init>(Socket.java:454) ~[na:na]
        at java.base/java.net.Socket.<init>(Socket.java:231) ~[na:na]
        at org.hsqldb.server.HsqlSocketFactory.createSocket(Unknown Source) ~[hsqldb-2.4.1.jar:2.4.1]
        ... 5 common frames omitted

I just don’t understand why connection is refused.
Any idea on what is going on?

Hi,
HSQLDB server is not embedded into the CUBA app.
During development it is the CUBA Studio who automatically starts HSQLDB server when you open the project.
When you deploy application, you need to start HSQLDB server yourself if you want to use it for your application.

Note that HSQLDB is an in-memory database. It is only recommended to use for prototyping and demos. It’s not good for storing production data.