First shutdown any running instances of the DA and the ActiveMQ;
service dadaemon stop
service activemq stop
Then, delete the DA data sub-directory under the apache-karaf directory - <HOME_IMDataAggregator>/apache-karaf-2.4.3/data. For example;
rm -rf /opt/CA/IMDataAggregator/apache-karaf-2.4.3/data
Then restart the dadaemon and ActiveMQ.
NOTE: Use the rm -r command with caution as this will recursively delete all directories specified and their contents.