I checked out your app, there was a network connection error between your appnode and dbnode, which is why it couldn't connect. As far as I can tell this has resolved itself and your app should be up and running.
Note that the runtime tries to reconnect automatically when it can't reach the dbnode, so if this ever happens again you should be able to just wait and have it resolve itself.
I experienced the same issue on the cloud environment that is used only by me.
Every time it happened when the same action is repeated and also I received the alert from Mendix that says that Database service went out of memory. The good thing is that the app continues its work as usual but it's not clear why I'm getting into the issue because the same actions were performed in the past and there were no problems.
Any idea what went wrong? :)
Thanks in advance,
org.hibernate.exception.GenericJDBCException: Cannot open connection
Sep 13 21:10:27.973 - ERROR - getVPRelation: (72/494) Caused by: java.sql.SQLException: Cannot get new connection for user null from database driver: java.sql.SQLException: Listener refused the connection with the following error:
Sep 13 21:11:25.187 - ERROR - ConnectionBus_Retrieve: JDBCDataStore::execRetrieveQuery failed with SQLState: 08006, error code: 0, message: An I/O error occurred while sending to the backend.
Sep 13 21:11:25.190 - ERROR - ConnectionBus_Retrieve: (1/125) org.postgresql.util.PSQLException: An I/O error occurred while sending to the backend.
Sep 13 21:11:25.190 - ERROR - ConnectionBus_Retrieve: (2/125) #011at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:318)
Sep 13 21:11:25.190 - ERROR - ConnectionBus_Retrieve: (3/125) #011at org.postgresql.jdbc.PgStatement.executeInternal(PgStatement.java:432)
What database do you use and is there any additional services? Because I run my SQL database from this database management company at work and I haven’t experienced any problems with connections so far.