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 Horizon with all built-in dependencies sudo yum -y install opennms If you want time series trending and forecast functions you must install the R project packages. The additional download size for packages is ~390 MB. Install R-core packages for time series trending and forecasting (optional) sudo yum -y install epel-release sudo yum -y install R-core 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. We recommend that you exclude the Horizon packages from update except when you plan to perform an upgrade. Disable auto updates for OpenNMS Horizon 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/opennms -L 1 Directory structure after successful installation /opt/opennms ├── bin ├── contrib ├── data ├── deploy ├── etc ├── jetty-webapps ├── lib ├── logs -> /var/log/opennms ├── share -> /var/opennms └── system