In order to set agent in active mode: 1.Check connection to ProxyServer (telnet Proxyserver 10051) 2.In zabbix_agentd.conf set ServerActive parameter to the IP/DNS name of the Proxyserver 3.Restart zabbix_agentd and check log for issues 4.Install zabbix sender on the host server # rpm -Uvh https://repo.zabbix.com/zabbix/6.4/rhel/7/x86_64/zabbix-release-6.4-1.el7.noarch.rpm # yum install zabbix-sender -y