Zabbix is an Open-source monitoring tool use to monitor the health of servers, networks and other IT units. Zabbix provides a web-based GUI to monitor your device Reports. Users can also set a mailing system to receive Reports as well.

If your Internal Zabbix Monitoring System is on Version 3.0, in this case, you will need to install Zabbix repo with version 3 or Zabbix agent will not connect with Zabbix Server.

Following are the steps to install Zabbix Agent 3 on Debian 9 (stretch).

1. Download the Zabbix Repository using wget command from Zabbix Website. We will install Zabbix agent version 3 for Debian 9 (stretch) using below Commands.
   
   

   # wget https://repo.zabbix.com/zabbix/3.0/debian/pool/main/z/zabbix-release/zabbix-release_3.0-2+stretch_all.deb 

   dpkg -i zabbix-release_3.0-2+stretch_all.deb
   

2. Create a File named preference at location /etc/apt/ and add the below lines. It will prevent the Zabbix repo to be upgraded from 3.0 to 4.0 while running apt-get update. If you don't do this, Zabbix repo will be upgraded automatically to 4.0 and you will face issues in the connectivity of your Zabbix server.
   
   

   Package: zabbix-*
   Pin: origin repo.zabbix.com						
   Pin-Priority: 900
   

3. Run the update command.
   
   

   # apt-get update
   

4. Install Zabbix Agent.
   
   

   # apt-get install zabbix-agent - Y
   

5. Once the Zabbix agent is installed. We will need to proceed to configure Zabbix.
   
   
6. To configure Zabbix agent, please go to file /etc/zabbix/zabbix_agentd.conf and update your Zabbix sever ip Address, server Active IP Address and server hostname.
   
   

   # sudo nano /etc/zabbix/zabbix_agentd.conf

   
   
   
   
   
   
   
   
7. Let us restart the Zabbix Agent Service.
   
   

   # sudo systemctl enable zabbix-agent 
   # sudo systemctl start zabbix-agent 
   

          You have successfully installed Zabbix Agent version 3.0 on Debian 9 (Stretch).