nethserver-zabbix integrates the newest Zabbix monitoring system from Zabbix repo to NethServer
Install Zabbix 5.0 LTS repo:
yum -y install https://repo.zabbix.com/zabbix/5.0/rhel/7/x86_64/zabbix-release-5.0-1.el7.noarch.rpm
Browse to /zabbix and login with user Admin and password zabbix.