when i am using grails 2.1.1
i use this to configure jndi datasource
in config.groovy
 grails.naming.entries = [
    "jdbc/notifDS": [
        auth: "Container",
        type: "javax.sql.DataSource",
        maxActive: "50",
        maxIdle: "25",
        minIdle: "5",
        initialSize: "5",
        maxWait: "10000",
        validationQuery: "SELECT 1",
        timeBetweenEvictionRunsMillis: "60000",
        minEvictableIdleTimeMillis: "60000",
        username: "root",
        password: "root",
        driverClassName: "com.mysql.jdbc.Driver",
        url: "jdbc:mysql://localhost:3306/notif?autoReconnect=true"
    ]  
]
and in datasource.groovy
dataSource {
            dbCreate = "update" 
            jndiName = "java:comp/env/jdbc/testJNDIDataSource"
            dialect = "org.hibernate.dialect.MySQL5InnoDBDialect"
        }
how about in grails 3.x.x ?