yeah, The proxy datasource tries to auto detect the database type through DatabaseMetaData and it seems it requires connection. otherwise, I would see (on JobRepository initialization) :

Caused by: org.springframework.jdbc.support.MetaDataAccessException: Error while extracting DatabaseMetaData; nested exception is java.sql.SQLTransientConnectionException: java.net.ConnectException: Connection refused
	at org.springframework.jdbc.support.JdbcUtils.extractDatabaseMetaData(JdbcUtils.java:296)