Your Horizon repository is defined in a file in /etc/apt/sources.list.

It may be named opennms-repo-stable-<OSversion>.repo but is not guaranteed to be.

  1. Become root.

  2. Enable auto updates:

    sudo apt-mark unhold libopennms-java \
                  libopennmsdeps-java \
                  opennms-common \
                  opennms-db
  3. Purge any cached data:

    apt-get clean
  4. Make a backup copy of your OpenNMS config:

    rsync -Ppav ${OPENNMS_HOME}/etc /tmp/etc.orig
    rsync -Ppav ${OPENNMS_HOME}/jetty-webapps/opennms/WEB-INF /tmp/opennms-web-inf
  5. Upgrade the Horizon packages to the new version:

    apt-get upgrade opennms
  6. Disable auto updates:

    sudo apt-mark hold libopennms-java \
                  libopennmsdeps-java \
                  opennms-common \
                  opennms-db
  7. Upgrade Java 11 to the latest release:

    apt-get install java-11-openjdk java-11-openjdk-devel
  8. Execute runjava to update which JVM Horizon will use:

    ${OPENNMS_HOME}/bin/runjava -s
  9. Check for configuration file changes, and update accordingly, using the files you backed up in Idenfity Changed Configuration Files.

    Debian prompts you to keep or overwrite your files during the apt upgrade process. Inspect these files manually and reconcile the differences. Use diff -Bbw and diff -y to look for changes.
  10. Run the Horizon installer:

    ${OPENNMS_HOME}/bin/install -dis

    The upgrade may take some time. The message Upgrade completed successfully! will confirm the upgrade has completed. If you do not get this message, check the output of the install command for any error messages.

  11. Clear the Karaf cache:

    yes | ${OPENNMS_HOME}/bin/fix-karaf-setup.sh
  12. Start OpenNMS Horizon:

    systemctl start opennms.service
    tail -F ${OPENNMS_HOME}/logs/manager.log can illustrate the current point in the startup process Horizon is.
  13. Upgrade is complete and operation is resumed.