sudo systemctl stop opennms

sudo tar --exclude='usr/share/opennms/data/cache' -cvzf /tmp/opennms-usr-share.tar.gz /usr/share/opennms && \
sudo tar -cvzf /tmp/opennms-etc.tar.gz /etc/opennms && \
sudo tar -cvzf /tmp/opennms-var-lib.tar.gz /var/lib/opennms && \
sudo tar -cvzf /tmp/opennms-usr-share-java.tar.gz /usr/share/java/opennms

sudo runuser -l postgres -c 'pg_dumpall -f /tmp/opennms-postgres.dmp'

sudo grep opennms /etc/passwd > /tmp/opennms-passwd.txt && \
sudo grep opennms /etc/group > /tmp/opennms-group.txt