Major Description
In smoke test, Hadoop code is placed in /opt/hadoop, and Ozone code is placed in /opt/ozone.
There are two copies of core-site.xml, one in $HADOOP_CONF_DIR, and another one in $OZONE_CONF_DIR. When user look at the copy in $OZONE_CONF_DIR, core-site.xml is empty. This may lead to assumption that hadoop is running with local file system. Most application will reference to core-site.xml on the classpath. Hence, it depends on how the application is carefully setup to avoid using $OZONE_CONF_DIR as a single node Hadoop. It may make sense to symlink $OZONE_CONF_DIR to $HADOOP_CONF_DIR to prevent mistakes.