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You must have a well-formatted db_config.xml present in the volume you are mounting. See the db_config.xml below for an example of one that is well-formatted. You can copy the example below into the volume you are mounting if you prefer; whatever configuration you need to do will be done within the application itself. Note that if the url URL JDBC string is for MariaDB, MySQL, or Oracle, then your CTP deployment/pod should be configured with the correct JDBC adapter or it won't start up properly; if the url URL JDBC string is for HyperSQL, it should start up regardless of your CTP deployment/pod configuration.
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