Steps to Install Nagios 4 on Debian 9. Nagios is an open source server and network monitoring tool which monitors some services CPU, HTTP, SMTP, storage disk, temperature, etc of your servers, network devices and alerts you when a particular service thats being monitored goes wrong. Pablo Escobar Daughter. It will also alert you when a service comes back to a normal required state. Nagios is useful for keeping an inventory of your server and making sure your critical services are up and running. How does nagios work Nagios runs in agent based and agentless configurations. A user friendly, web based graphical user interface is provided in some versions of Nagios and from third parties like Nagios. QL, or an administrator can choose to work in the command line interface. It also comes with a dashboard that provides an overview of the critical parameters monitored on assets. This article explains step by step on how to install nagios on debian 9 in order to monitor your server and its services. In this tutorial we will discuss how to install VirtualBox 5. CentOS 7, RHEL 7 and Fedora 26. The installation of nagios requires the steps belowapache and php installed with some other pre requisites packages which will be listed on the articlethe creation of a nagios userthe installation and configuration of nagios corethe configuration of the nagios web interfacethe installation and configuration of the nagios pluginsthe configuration of the firewall. In another article, we have shown how to install Nagios on centos 7. Install Debian 7' title='Install Debian 7' />Now lets explain step to follow in order to install nagios on debian 9 with detailed information. Install pre requisites. To have nagios well working, you need apache. If you have not yet these packages installed, you can do it with the command below. In this article, the configuration of the above packages will be not detailed. There are some other pre requisites packages to install as below apt install y build essential autoconf gcc libc. Create Nagios user and group. Youll need a default user and group on nagios for the system to run under. The default user will be nagios and the default group will be nagcmd. You can turn off logins for this user once everything is installed useradd nagios groupadd nagcmd. G nagcmd nagios usermod a G nagcmd www data. Install and build Nagios 4. Download nagios. We will download nagios from the official github site. We will create our working directory at optnagios mkdir optnagios cd optnagios. Now download nagios wget O nagioscore. Nagios. Enterprisesnagioscorearchivenagios 4. Install and configure nagios. Now we will configure, compile and install nagios. You can that it helps you by giving you next configurations steps to follow and description. Now we will install the binary files, CGIs, and HTML files make install. We will install the service or daemon files and also configure them to start on boot make install init. Now install and configure the external command file make install commandmode. Now install the SAMPLEconfiguration files. These are required as Nagios needs some configuration files to allow it to start. Then install the Apache web server configuration files and configure the Apache settings. Configure nagios web interface. Debian_7.0/install/img/17.jpg' alt='Install Debian 7' title='Install Debian 7' />This tutorial will show you how to install and configure the latest version of Nagios Core, currently 4. Debian 9. 1, codename Stre. Debian Install Java 8. How to Install JAVA 8 on Debian via PPA. Install Oracle JAVA 8 JDKJRE 8u144 on Debian system using PPA. Java 8 Install Debian PPA. OpenSUSE packages. SUSE ships with Darktable. A simple zypper install darktable should be enough. If you want the latest stable version you can use Darktable. The web interface requires login so we will create a nagiosadmin account and record the password that we will assign htpasswd c usrlocalnagiosetchtpasswd. Re type new password Notice that you will use this user and password to log into you nagios web interface. Now restart apache service to make modifications to take effect systemctl restart apache. Download and install nagios plugins 2. To work properly, nagios core needs plugins to monitor various services. You need to make sure that you have the pre requisites packages installed apt install y autoconf gcc libc. Now we will create our working directory into opt directory where we will download the plugins mkdir optnagios  cd optnagios wget no check certificate O nagios plugins. Now we will compile and install the plugins. Start nagios service and access to your nagios server. Before starting nagios, we need to check if the nagios configuration file doesnt have any error usrlocalnagiosbinnagios v usrlocalnagiosetcnagios. Total Warnings 0. Total Errors 0. Things look okay No serious problems were detected during the pre flight check. As it looks fine, now lets make nagios services start on startup systemctl enable nagios systemctl reload nagios. Now we can start the nagios service systemctl start nagios. Note that if you dont start the nagios service, you will have an error message at you nagios homepage. Now you can access to your web interface at the address http nagios ipnagios via your web browser. If you server has an interface environment, so you can open your web browser and use the link http localhostnagios. You will be asked to enter the username and the password. Below are the values that I have configuredusername nagiosadminpassword nagios. Then you will have the following homepage. Why Does My Jelly Roll Cake Crack there. Now you can go to Hosts or Services menu list to the left side in order to see you server and services monitored. You can see that the default monitored services of our server. Configure Firewall. If you can not access to your web interface, you should check your firewall configuration. By default on Debian 9, it seems that ufw is not installed but iptables is installed. So, you will certainly need to allow port 8. I INPUT p tcp destination port 8. ACCEPT apt install y iptables persistent. Save the firewall configuration iptables save. But if you prefer ufw as firewall instead of iptables, use the command below ufw allow Apache ufw reload. Now restart all service again to check systemctl restart nagios systemctl restart apache. Conclusion. Now that you monitoring your server and some of its services. Nagios has proven popular among small and large businesses. If you want to be proactive, have peace of mind, and sleep well at night, you should implement a robust system and network monitoring solution for your IT infrastructure.