UbuntuDebianSLESRHEL

apt install \
    icinga2 \
    icingacli \
    icingadb \
    icingadb-redis \
    icingadb-web \
    icingaweb2 \
    icinga-director \
    monitoring-plugins 

apt install \
    icinga2 \
    icingacli \
    icingadb \
    icingadb-redis \
    icingadb-web \
    icingaweb2 \
    icinga-director \
    monitoring-plugins

zypper install \
    icinga2 \
    icingacli \
    icingadb \
    icingadb-redis \
    icingadb-web \
    icingaweb2 \
    icinga-director

zypper install --recommends monitoring-plugins-all

The packages for RHEL depend on other packages which are distributed as part of the EPEL repository.

dnf install \
    icinga2 \
    icingacli \
    icingadb \
    icingadb-redis \
    icingadb-web \
    icingaweb2 \
    icinga-director \
    nagios-plugins-all

systemctl enable --now icinga2

Warning

If SELinux is enabled on your server, you may have to allow connections from the web server to Redis® explicitly.

setsebool -P httpd_can_network_connect 1

and install additional packages to configure SELinux properly:

dnf install icinga-selinux-common icingaweb2-selinux icinga2-selinux