# About Icinga 2 <a id="about-icinga2"></a>

## What is Icinga 2?  <a id="what-is-icinga2"></a>

[Icinga 2](https://icinga.com/products/icinga-2/) is a monitoring system which checks
the availability of your network resources, notifies users of outages, and generates
performance data for reporting.

Scalable and extensible, Icinga 2 can monitor large, complex environments across
multiple locations.

Icinga 2 as core requires [Icinga Web 2](https://icinga.com/products/icinga-web-2/)
on top in your Icinga Stack.


![Icinga 2 Distributed Master and Satellites with Agents](images/distributed-monitoring/icinga2_distributed_monitoring_scenarios_master_satellites_agents.png)

## Start with Icinga <a id="start-icinga"></a>

* [Installation](02-installation.md#installation)
* [Monitoring Basics](03-monitoring-basics.md#monitoring-basics)
* [Configuration](04-configuration.md#configuration)
* [Distributed Monitoring](06-distributed-monitoring.md#distributed-monitoring)
* [Addons, Integrations and Features](13-addons.md#addons)
* [Troubleshooting](15-troubleshooting.md#troubleshooting)
* [Upgrading](16-upgrading-icinga-2.md#upgrading-icinga-2)

Once Icinga Core and Web are running in your distributed environment,
make sure to check out the many [Icinga modules](https://icinga.com/docs/)
for even better monitoring.

## What's New <a id="whats-new"></a>

You can follow the development and release milestones on [GitHub](https://github.com/icinga/icinga2/issues).
Please follow our release announcements on [icinga.com](https://icinga.com/blog/) too.

## Support <a id="support"></a>

Check the project website at [icinga.com](https://icinga.com) for status updates. Join the
[community channels](https://icinga.com/community/) for questions
or get in touch for [professional support](https://icinga.com/subscription/).

## Contribute  <a id="contribute"></a>

There are many ways to contribute to Icinga -- whether it be sending patches,
testing, reporting bugs or reviewing and updating the documentation. Every
contribution is appreciated!

Please continue reading in the [Contributing chapter](https://github.com/Icinga/icinga2/blob/master/CONTRIBUTING.md).

### Security Issues <a id="security"></a>

For reporting security issues please visit [this page](https://icinga.com/contact/security/).

### Icinga 2 Development <a id="development-info"></a>

The Git repository is located on [GitHub](https://github.com/Icinga/icinga2).

Icinga 2 is written in C++ and can be built on Linux/Unix and Windows.
Read more about development builds in the [development chapter](21-development.md#development).


## License <a id="license"></a>

Icinga 2 and the Icinga 2 documentation are licensed under the terms of the GNU
General Public License Version 2. You will find a copy of this license in the
LICENSE file included in the source package.