Install OpenJDK 11 JRE runtime sudo yum -y install java-11-openjdk-headless Add repository and import GPG key sudo yum -y install https://yum.opennms.org/repofiles/opennms-repo-stable-rhel7.noarch.rpm sudo rpm --import https://yum.opennms.org/OPENNMS-GPG-KEY Install the Horizon Minion package sudo yum -y install opennms-minion Disable the OpenNMS Horizon repository after installation to prevent unwanted upgrades when upgrading other packages on the server. After upgrade, Horizon requires manual steps to upgrade configuration files or migrate database schemas to a new version. For this reason, we recommend that you exclude the Horizon packages from update except when you plan to perform an upgrade. Disable auto updates for Horizon Minion sudo yum -y install yum-utils sudo yum-config-manager --disable opennms-repo-stable-* Verify directory structure with the tree command sudo yum -y install tree tree /opt/minion -L 1 Directory structure after successful installation /opt/minion ├── bin ├── COPYING ├── deploy ├── etc ├── lib ├── repositories └── system Enable Horizon Minion on system boot and start immediately sudo systemctl enable --now minion