Technolead

   “It is an open source continuous monitoring tool which monitors network, applications and servers.” • It allows you to detect and repair problems and mitigate future issues before they affect end-users and customers • It is developed for monitoring servers, applications and networks • It provides a centralized view of your entire IT infrastructure and detailed up-to-date status information Features of Nagios Nagios Architecture Learn more about Nagios here : Installation & Configuration Plugins Notifocations GUI Web Console

 Exercise - Installing & Configuring Nagios Before beginning the work on Nagios you need to install Nagios Section 1 – Nagios Installation 1. You must have superuser privileges on the Ubuntu 14.04 server that will run Nagios. Ideally, you will be using a non-root user with superuser privileges. 2. A LAMP stack is also required. 3. Install Apache sudo apt-get update sudo apt-get install apache2 You can do a spot check right away to verify that everything went as planned by visiting your server's public IP address in your web browser (see the note under the next heading to find out what your public IP address is if you do not have this information already): http://your_server_IP_address You will see the default Ubuntu 14.04 Apache web page 4. Install MySQL sudo apt-get install mysql-server php5-mysql sudo mysql_install_db sudo mysql_secure_installation You will be asked to enter the password you set for the MySQL root account. 5. Install PHP sudo apt-get install php5 libapache2-m

 • Plugins are compiled executables or scripts(Perl or non-Perl) that extends Nagios functionality to monitor servers and hosts • Nagios will execute a Plugin to check the status of a service or host • Nagios can be compiled with support for an embedded Perl interpreter to execute Perl plugins • Without it, Nagios executes Perl and non-Perl plugins by forking and executing the plugins as an external command Nagios Remote Plugin Executor (NRPE) • NRPE allows you to remotely execute Nagios plugins on other Linux/Unix machines. This allows you to monitor remote machine metrics such as disk usage, CPU load etc • It can communicate with some of the Windows agent addons, so you can execute scripts and check metrics on remote Windows machines as well Nagios Remote Data Processor • Nagios Remote Data Processor (NRDP) is an agent which allows flexible data transport • It uses standard protocols such as: https:// , XML 

 • The decision to send out notifications is made in the service check and host check logic • Each host and service definition has a <contact_groups> option that specifies what contact groups receive notifications for that particular host or service • There are several filters that notifications encounters before reaching to the receiver Prerequisites for delivering notification  Nagios supports optional detection of hosts and services that are "flapping"  Flapping occurs when a service or host changes state too frequently, resulting a problem and recovery notifications Nagios Notification Methods • There are many ways through which Nagios notifies about a problem or recovery Example: Mail, Instant message, Audio alert etc. • How notifications are sent depend on the notification commands that are defined in your object definition files • While writing your notification commands, you need to take into account what type of notification is occurring • The $NOTIFICATIONTY

   Nagios Server : Hosts Nagios Server : Services

  Git is an open source Distributed Version Control System(DVCS) which records changes made to the files laying emphasis on  speed ,  data integrity  and  distributed ,  non-linear workflows. Essential Glossary for handling Pull Request  Branch A branch is a parallel version of a repository. It is contained within the repository, but does not affect the primary or master branch allowing you to work freely without disrupting the "live" version. When you've made the changes you want to make, you can merge your branch back into the master branch to publish your changes.   Branch restriction A restriction that repository admins can enable so that only certain users or teams can push or make certain changes to the branch. Checkout You can use git checkout on the command line to create a new branch, change your current working branch to a different branch, or even to switch to a different version of a file from a different branch with git checkout [branchname] [path to file]. T