Documentation: Clarify on DB IDO upgrades

[icinga2] / doc / 2-getting-started.md

# <a id="getting-started"></a> Getting Started

This tutorial is a step-by-step introduction to installing Icinga 2 and
available Icinga web interfaces. It assumes that you are familiar with
the system you're installing Icinga 2 on.

Details on troubleshooting problems can be found [here](#troubleshooting).

## <a id="setting-up-icinga2"></a> Setting up Icinga 2

First off you will have to install Icinga 2. The preferred way of doing this
is to use the official package repositories depending on which operating system
and distribution you are running.

  Distribution            | Repository
  ------------------------|---------------------------
  Debian                  | [Upstream](https://packages.debian.org/sid/icinga2), [DebMon](http://debmon.org/packages/debmon-wheezy/icinga2), [Icinga Repository](http://packages.icinga.org/debian/)
  Ubuntu                  | [Upstream](https://launchpad.net/ubuntu/+source/icinga2), [Icinga PPA](https://launchpad.net/~formorer/+archive/ubuntu/icinga), [Icinga Repository](http://packages.icinga.org/ubuntu/)
  RHEL/CentOS             | [Icinga Repository](http://packages.icinga.org/epel/)
  OpenSUSE                | [Icinga Repository](http://packages.icinga.org/openSUSE/), [Server Monitoring Repository](https://build.opensuse.org/package/show/server:monitoring/icinga2)
  SLES                    | [Icinga Repository](http://packages.icinga.org/SUSE/)
  Gentoo                  | [Upstream](http://packages.gentoo.org/package/net-analyzer/icinga2)
  FreeBSD                 | [Upstream](http://www.freshports.org/net-mgmt/icinga2)
  ArchLinux               | [Upstream](https://aur.archlinux.org/packages/icinga2)

Packages for distributions other than the ones listed above may also be
available. Please contact your distribution packagers.

### <a id="installing-requirements"></a> Installing Requirements for Icinga 2

You need to add the Icinga repository to your package management configuration.
Below is a list with examples for the various distributions.

Debian (debmon):

    # wget -O - http://debmon.org/debmon/repo.key 2>/dev/null | apt-key add -
    # cat >/etc/apt/sources.list.d/debmon.list<<EOF
    deb http://debmon.org/debmon debmon-wheezy main
    EOF
    # apt-get update

Ubuntu (PPA):

    # add-apt-repository ppa:formorer/icinga
    # apt-get update

RHEL/CentOS:

    # rpm --import http://packages.icinga.org/icinga.key
    # wget http://packages.icinga.org/epel/ICINGA-release.repo -O /etc/yum.repos.d/ICINGA-release.repo
    # yum makecache

Fedora:

    # wget http://packages.icinga.org/fedora/ICINGA-release.repo -O /etc/yum.repos.d/ICINGA-release.repo
    # yum makecache

SLES:

    # zypper ar http://packages.icinga.org/SUSE/ICINGA-release.repo
    # zypper ref

OpenSUSE:

    # zypper ar http://packages.icinga.org/openSUSE/ICINGA-release.repo
    # zypper ref

The packages for RHEL/CentOS depend on other packages which are distributed
as part of the [EPEL repository](http://fedoraproject.org/wiki/EPEL). Please
make sure to enable this repository by following
[these instructions](#http://fedoraproject.org/wiki/EPEL#How_can_I_use_these_extra_packages.3F).

### <a id="installing-icinga2"></a> Installing Icinga 2

You can install Icinga 2 by using your distribution's package manager
to install the `icinga2` package.

Debian/Ubuntu:

    # apt-get install icinga2

RHEL/CentOS/Fedora:

    # yum install icinga2

SLES/OpenSUSE:

    # zypper install icinga2

On RHEL/CentOS and SLES you will need to use `chkconfig` to enable the
`icinga2` service. You can manually start Icinga 2 using `service icinga2 start`.

    # chkconfig icinga2 on
    # service icinga2 start

RHEL/CentOS 7 use [Systemd](#systemd-service) with `systemctl {enable,start} icinga2`.

    # systemctl enable icinga2
    # systemctl start icinga2

Some parts of Icinga 2's functionality are available as separate packages:

  Name                    | Description
  ------------------------|--------------------------------
  icinga2-ido-mysql       | [DB IDO](#configuring-db-ido) provider module for MySQL
  icinga2-ido-pgsql       | [DB IDO](#configuring-db-ido) provider module for PostgreSQL

If you're running a distribution for which Icinga 2 packages are
not yet available you will need to use the release tarball which you
can download from the [Icinga website](https://www.icinga.org/). The
release tarballs contain an `INSTALL` file with further instructions.

### <a id="installation-enabled-features"></a> Enabled Features during Installation

The default installation will enable three features required for a basic
Icinga 2 installation:

* `checker` for executing checks
* `notification` for sending notifications
* `mainlog` for writing the `icinga2.log ` file

Verify that by calling `icinga2-enable-feature` without any additional parameters
and enable the missing features, if any.

    # icinga2-enable-feature
    Syntax: icinga2-enable-feature <features separated with whitespaces>
      Example: icinga2-enable-feature checker notification mainlog
    Enables the specified feature(s).

    Available features: api checker command compatlog debuglog graphite icingastatus ido-mysql ido-pgsql livestatus mainlog notification perfdata statusdata syslog
    Enabled features: checker mainlog notification

### <a id="installation-paths"></a> Installation Paths

By default Icinga 2 uses the following files and directories:

  Path                                | Description
  ------------------------------------|------------------------------------
  /etc/icinga2                        | Contains Icinga 2 configuration files.
  /etc/init.d/icinga2                 | The Icinga 2 init script.
  /usr/bin/icinga2-*                  | Migration and certificate build scripts.
  /usr/sbin/icinga2*                  | The Icinga 2 binary and feature enable/disable scripts.
  /usr/share/doc/icinga2              | Documentation files that come with Icinga 2.
  /usr/share/icinga2/include          | The Icinga Template Library and plugin command configuration.
  /var/run/icinga2                    | PID file.
  /var/run/icinga2/cmd                | Command pipe and Livestatus socket.
  /var/cache/icinga2                  | status.dat/objects.cache.
  /var/spool/icinga2                  | Used for performance data spool files.
  /var/lib/icinga2                    | Icinga 2 state file, cluster feature replay log and configuration files.
  /var/log/icinga2                    | Log file location and compat/ directory for the CompatLogger feature.

## <a id="setting-up-check-plugins"></a> Setting up Check Plugins

Without plugins Icinga 2 does not know how to check external services. The
[Monitoring Plugins Project](https://www.monitoring-plugins.org/) provides
an extensive set of plugins which can be used with Icinga 2 to check whether
services are working properly.

The recommended way of installing these standard plugins is to use your
distribution's package manager.

> **Note**
>
> The `Nagios Plugins` project was renamed to `Monitoring Plugins`
> in January 2014. At the time of this writing some packages are still
> using the old name while some distributions have adopted the new package
> name `monitoring-plugins` already.

> **Note**
>
> EPEL for RHEL/CentOS 7 is still in beta mode at the time of writing and does
> not provide a `monitoring-plugins` package. You are required to manually install
> them.

For your convenience here is a list of package names for some of the more
popular operating systems/distributions:

OS/Distribution        | Package Name       | Installation Path
-----------------------|--------------------|---------------------------
RHEL/CentOS (EPEL)     | nagios-plugins-all | /usr/lib/nagios/plugins or /usr/lib64/nagios/plugins
Debian                 | nagios-plugins     | /usr/lib/nagios/plugins
FreeBSD                | nagios-plugins     | /usr/local/libexec/nagios
OS X (MacPorts)        | nagios-plugins     | /opt/local/libexec

Depending on which directory your plugins are installed into you may need to
update the global `PluginDir` constant in your Icinga 2 configuration. This macro is used
by the service templates contained in the Icinga Template Library to determine
where to find the plugin binaries.

### <a id="integrate-additional-plugins"></a> Integrate Additional Plugins

For some services you may need additional 'check plugins' which are not provided
by the official Monitoring Plugins project.

All existing Nagios or Icinga 1.x plugins work with Icinga 2. Here's a
list of popular community sites which host check plugins:

* [MonitoringExchange](https://www.monitoringexchange.org)
* [Icinga Wiki](https://wiki.icinga.org)

The recommended way of setting up these plugins is to copy them to a common directory
and create an extra global constant, e.g. `CustomPluginDir` in your [constants.conf](#constants-conf)
configuration file:

    # cp check_snmp_int.pl /opt/plugins
    # chmod +x /opt/plugins/check_snmp_int.pl

    # cat /etc/icinga2/constants.conf
    /**
     * This file defines global constants which can be used in
     * the other configuration files. At a minimum the
     * PluginDir constant should be defined.
     */

    const PluginDir = "/usr/lib/nagios/plugins"
    const CustomPluginDir = "/opt/monitoring"

Prior to using the check plugin with Icinga 2 you should ensure that it is working properly
by trying to run it on the console using whichever user Icinga 2 is running as:

    # su - icinga -s /bin/bash
    $ /opt/plugins/check_snmp_int.pl --help

Additional libraries may be required for some plugins. Please consult the plugin
documentation and/or plugin provided README for installation instructions.

Each plugin requires a [CheckCommand](#objecttype-checkcommand) object in your
configuration which can be used in the [Service](#objecttype-service) or
[Host](#objecttype-host) object definition. Examples for `CheckCommand`
objects can be found in the [Plugin Check Commands](#plugin-check-commands) shipped
with Icinga 2.
For further information on your monitoring configuration read the
[monitoring basics](#monitoring-basics).


## <a id="configuring-icinga2-first-steps"></a> Configuring Icinga 2: First Steps

### <a id="icinga2-conf"></a> icinga2.conf

An example configuration file is installed for you in `/etc/icinga2/icinga2.conf`.

Here's a brief description of the example configuration:

    /**
     * Icinga 2 configuration file
     * - this is where you define settings for the Icinga application including
     * which hosts/services to check.
     *
     * For an overview of all available configuration options please refer
     * to the documentation that is distributed as part of Icinga 2.
     */

Icinga 2 supports [C/C++-style comments](#comments).

    /**
     * The constants.conf defines global constants.
     */
    include "constants.conf"

The `include` directive can be used to include other files.

    /**
     * The zones.conf defines zones for a cluster setup.
     * Not required for single instance setups.
     */
     include "zones.conf"

    /**
     * The Icinga Template Library (ITL) provides a number of useful templates
     * and command definitions.
     * Common monitoring plugin command definitions are included separately.
     */
    include <itl>
    include <plugins>

    /**
     * The features-available directory contains a number of configuration
     * files for features which can be enabled and disabled using the
     * icinga2-enable-feature / icinga2-disable-feature tools. These two tools work by creating
     * and removing symbolic links in the features-enabled directory.
     */
    include "features-enabled/*.conf"

This `include` directive takes care of including the configuration files for all
the features which have been enabled with `icinga2-enable-feature`. See
[Enabling/Disabling Features](#features) for more details.

    /**
     * Although in theory you could define all your objects in this file
     * the preferred way is to create separate directories and files in the conf.d
     * directory. Each of these files must have the file extension ".conf".
     */
    include_recursive "conf.d"

You can put your own configuration files in the `conf.d` directory. This
directive makes sure that all of your own configuration files are included.

### <a id="constants-conf"></a> constants.conf

The `constants.conf` configuration file can be used to define global constants:

    /**
     * This file defines global constants which can be used in
     * the other configuration files.
     */

    /* The directory which contains the plugins from the Monitoring Plugins project. */
    const PluginDir = "/usr/lib/nagios/plugins"

    /* Our local instance name. This should be the common name from the API certificate */
    const NodeName = "localhost"

    /* Our local zone name. */
    const ZoneName = NodeName

### <a id="zones-conf"></a> zones.conf

The `zones.conf` configuration file can be used to configure `Endpoint` and `Zone` objects
required for a [distributed zone setup](#distributed-monitoring-high-availability). By default
a local dummy zone is defined based on the `NodeName` constant defined in
[constants.conf](#constants-conf).

> **Note**
>
> Not required for single instance installations.


### <a id="localhost-conf"></a> localhost.conf

The `conf.d/hosts/localhost.conf` file contains our first host definition:

    /**
     * A host definition. You can create your own configuration files
     * in the conf.d directory (e.g. one per host). By default all *.conf
     * files in this directory are included.
     */

    object Host "localhost" {
      import "generic-host"

      address = "127.0.0.1"
      address6 = "::1"

      vars.os = "Linux"
      vars.sla = "24x7"
    }

This defines the host `localhost`. The `import` keyword is used to import
the `generic-host` template which takes care of setting up the host check
command to `hostalive`. If you require a different check command, you can
override it in the object definition.

The `vars` attribute can be used to define custom attributes which are available
for check and notification commands. Most of the templates in the Icinga
Template Library require an `address` attribute.

The custom attribute `os` is evaluated by the `linux-servers` group in
`groups.conf `making the host `localhost` a member.

    object HostGroup "linux-servers" {
      display_name = "Linux Servers"

      assign where host.vars.os == "Linux"
    }

A host notification apply rule in `notifications.conf` checks for the custom
attribute `sla` being set to `24x7` automatically applying a host notification.

    /**
     * The example notification apply rules.
     *
     * Only applied if host/service objects have
     * the custom attribute `sla` set to `24x7`.
     */

    apply Notification "mail-icingaadmin" to Host {
      import "mail-host-notification"

      user_groups = [ "icingaadmins" ]

      assign where host.vars.sla == "24x7"
    }

Now it's time to define services for the host object. Because these checks
are only available for the `localhost` host, they are organized below
`hosts/localhost/`.

> **Tip**
>
> The directory tree and file organisation is just an example. You are
> free to define your own strategy. Just keep in mind to include the
> main directories in the [icinga2.conf](#icinga2-conf) file.

    object Service "disk" {
      import "generic-service"

      host_name = "localhost"
      check_command = "disk"
      vars.sla = "24x7"
    }

    object Service "http" {
      import "generic-service"

      host_name = "localhost"
      check_command = "http"
      vars.sla = "24x7"
    }

    object Service "load" {
      import "generic-service"

      host_name = "localhost"
      check_command = "load"
      vars.sla = "24x7"
    }

    object Service "procs" {
      import "generic-service"

      host_name = "localhost"
      check_command = "procs"
      vars.sla = "24x7"
    }

    object Service "ssh" {
      import "generic-service"

      host_name = "localhost"
      check_command = "ssh"
      vars.sla = "24x7"
    }

    object Service "swap" {
      import "generic-service"

      host_name = "localhost"
      check_command = "swap"
      vars.sla = "24x7"
    }

    object Service "users" {
      import "generic-service"

      host_name = "localhost"
      check_command = "users"
      vars.sla = "24x7"
    }

    object Service "icinga" {
      import "generic-service"

      host_name = "localhost"
      check_command = "icinga"
      vars.sla = "24x7"
    }

The command object `icinga` for the embedded health check is provided by the
[Icinga Template Library (ITL)](#itl) while `http_ip`, `ssh`, `load`, `processes`,
`users` and `disk` are all provided by the plugin check commands which we enabled
earlier by including the `itl` and `plugins` configuration file.

The Debian packages also ship an additional `apt` service check.

> **Best Practice**
>
> Instead of defining each service object and assigning it to a host object
> using the `host_name` attribute rather use the [apply rules](#apply)
> simplifying your configuration.

There are two generic services applied to all hosts in the host group `linux-servers`
and `windows-servers` by default: `ping4` and `ping6`. Host objects without
a valid `address` resp. `address6` attribute will be excluded.

    apply Service "ping4" {
      import "generic-service"

      check_command = "ping4"
      vars.sla = "24x7"

      assign where "linux-servers" in host.groups
      assign where "windows-servers" in host.groups
      ignore where host.address == ""
    }

    apply Service "ping6" {
      import "generic-service"

      check_command = "ping6"
      vars.sla = "24x7"

      assign where "linux-servers" in host.groups
      assign where "windows-servers" in host.groups
      ignore where host.address6 == ""
    }

Each of these services has the custom attribute `sla` set to `24x7`. The
notification apply rule in `notifications.conf` will automatically apply
a service notification matchting this attribute pattern.

    apply Notification "mail-icingaadmin" to Service {
      import "mail-service-notification"

      user_groups = [ "icingaadmins" ]

      assign where service.vars.sla == "24x7"
    }

Don't forget to install the [check plugins](#setting-up-check-plugins) required by the services and
their check commands.

Further details on the monitoring configuration can be found in the
[monitoring basics](#monitoring-basics) chapter.

## <a id="configuring-db-ido"></a> Configuring DB IDO

The DB IDO (Database Icinga Data Output) modules for Icinga 2 take care of exporting
all configuration and status information into a database. The IDO database is used
by a number of projects including Icinga Web 1.x, Reporting or Icinga Web 2.

There is a separate module for each database back-end. At present support for
both MySQL and PostgreSQL is implemented.

Icinga 2 uses the Icinga 1.x IDOUtils database schema. Icinga 2 requires additional
features not yet released with older Icinga 1.x versions.

> **Note**
>
> Please check the [what's new](#whats-new) section for the required schema version.

> **Tip**
>
> Only install the IDO feature if your web interface or reporting tool requires
> you to do so (for example, [Icinga Web](#setting-up-icinga-web) or [Icinga Web 2](#setting-up-icingaweb2)).
> [Icinga Classic UI](#setting-up-icinga-classic-ui) does not use IDO as backend.

### <a id="installing-database"></a> Installing the Database Server

In order to use DB IDO you need to setup either [MySQL](#installing-database-mysql-server)
or [PostgreSQL](#installing-database-postgresql-server) as supported database server.

> **Note**
>
> It's up to you whether you choose to install it on the same server where Icinga 2 is running on,
> or on a dedicated database host (or cluster).

#### <a id="installing-database-mysql-server"></a> Installing MySQL database server

Debian/Ubuntu:

    # apt-get install mysql-server mysql-client

RHEL/CentOS 5/6:

    # yum install mysql-server mysql
    # chkconfig mysqld on
    # service mysqld start

RHEL/CentOS 7 and Fedora 20 prefer MariaDB over MySQL:

    # yum install mariadb-server mariadb
    # systemctl enable mariadb.service
    # systemctl start mariadb.service

SUSE:

    # zypper install mysql mysql-client
    # chkconfig mysqld on
    # service mysqld start

RHEL based distributions do not automatically set a secure root password. Do that **now**:

    # /usr/bin/mysql_secure_installation


#### <a id="installing-database-postgresql-server"></a> Installing PostgreSQL database server

Debian/Ubuntu:

    # apt-get install postgresql

RHEL/CentOS 5/6:

    # yum install postgresql-server postgresql
    # chkconfig postgresql on
    # service postgresql start

RHEL/CentOS 7 and Fedora 20 use [systemd](#systemd-service):

    # yum install postgresql-server postgresql
    # systemctl enable postgresql.service
    # systemctl start postgresql.service

SUSE:

    # zypper install postgresql postgresql-server
    # chkconfig postgresql on
    # service postgresql start

### <a id="configuring-db-ido-mysql"></a> Configuring DB IDO MySQL

First of all you have to install the `icinga2-ido-mysql` package using your
distribution's package manager.

Debian/Ubuntu:

    # apt-get install icinga2-ido-mysql

RHEL/CentOS:

    # yum install icinga2-ido-mysql

SUSE:

    # zypper install icinga2-ido-mysql



> **Note**
>
> Upstream Debian packages provide a database configuration wizard by default.
> You can skip the automated setup and install/upgrade the database manually
> if you prefer that.

#### <a id="setting-up-mysql-db"></a> Setting up the MySQL database

Set up a MySQL database for Icinga 2:

    # mysql -u root -p

    mysql>  CREATE DATABASE icinga;
            GRANT SELECT, INSERT, UPDATE, DELETE, DROP, CREATE VIEW, INDEX, EXECUTE ON icinga.* TO 'icinga'@'localhost' IDENTIFIED BY 'icinga';
            quit

After creating the database you can import the Icinga 2 IDO schema using the
following command:

    # mysql -u root -p icinga < /usr/share/icinga2-ido-mysql/schema/mysql.sql


#### <a id="upgrading-mysql-db"></a> Upgrading the MySQL database

Check the `/usr/share/icinga2-ido-mysql/schema/upgrade` directory for an
incremental schema upgrade file.

> **Note**
>
> If there isn't an upgrade file for your current version available there's nothing to do.

Apply all database schema upgrade files incrementially.

    # mysql -u root -p icinga < /usr/share/icinga2-ido-mysql/schema/upgrade/<version>.sql

The Icinga 2 DB IDO module will check for the required database schema version on startup
and generate an error message if not satisfied.


**Example:** You are upgrading Icinga 2 from version `2.0.2` to `2.1.0`. Look into
the *upgrade* directory:

    $ ls /usr/share/icinga2-ido-mysql/schema/upgrade/
    2.0.2.sql  2.1.0.sql

There is a new upgrade file called `2.1.0.sql` which must be applied to your IDO database.


#### <a id="installing-ido-mysql"></a> Installing the IDO MySQL module

The package provides a new configuration file that is installed in
`/etc/icinga2/features-available/ido-mysql.conf`. You will need to update the
database credentials in this file.

You can enable the `ido-mysql` feature configuration file using `icinga2-enable-feature`:

    # icinga2-enable-feature ido-mysql
    Module 'ido-mysql' was enabled.
    Make sure to restart Icinga 2 for these changes to take effect.

After enabling the ido-mysql feature you have to restart Icinga 2:

Debian/Ubuntu, RHEL/CentOS 6 and SUSE:

    # service icinga2 restart

RHEL/CentOS 7 and Fedora 20:

    # systemctl restart icinga2.service

### <a id="configuring-db-ido-postgresql"></a> Configuring DB IDO PostgreSQL

First of all you have to install the `icinga2-ido-pgsql` package using your
distribution's package manager.

Debian/Ubuntu:

    # apt-get install icinga2-ido-pgsql

RHEL/CentOS:

    # yum install icinga2-ido-pgsql

SUSE:

    # zypper install icinga2-ido-pgsql

> **Note**
>
> Upstream Debian packages provide a database configuration wizard by default.
> You can skip the automated setup and install/upgrade the database manually
> if you prefer that.

#### Setting up the PostgreSQL database

Set up a PostgreSQL database for Icinga 2:

    # cd /tmp
    # sudo -u postgres psql -c "CREATE ROLE icinga WITH LOGIN PASSWORD 'icinga'";
    # sudo -u postgres createdb -O icinga -E UTF8 icinga
    # sudo -u postgres createlang plpgsql icinga

> **Note**
>
> Using PostgreSQL 9.x you can omit the `createlang` command.

Locate your pg_hba.conf (Debian: `/etc/postgresql/*/main/pg_hba.conf`,
RHEL/SUSE: `/var/lib/pgsql/data/pg_hba.conf`), add the icinga user with md5
authentication method and restart the postgresql server.

    # vim /var/lib/pgsql/data/pg_hba.conf

    # icinga
    local   icinga      icinga                            md5
    host    icinga      icinga      127.0.0.1/32          md5
    host    icinga      icinga      ::1/128               md5

    # "local" is for Unix domain socket connections only
    local   all         all                               ident
    # IPv4 local connections:
    host    all         all         127.0.0.1/32          ident
    # IPv6 local connections:
    host    all         all         ::1/128               ident

    # /etc/init.d/postgresql restart


After creating the database and permissions you can import the Icinga 2 IDO schema
using the following command:

    # export PGPASSWORD=icinga
    # psql -U icinga -d icinga < /usr/share/icinga2-ido-pgsql/schema/pgsql.sql

#### <a id="upgrading-postgresql-db"></a> Upgrading the PostgreSQL database

Check the `/usr/share/icinga2-ido-pgsql/schema/upgrade` directory for an
incremental schema upgrade file.

> **Note**
>
> If there isn't an upgrade file for your current version available there's nothing to do.

Apply all database schema upgrade files incrementially.

    # export PGPASSWORD=icinga
    # psql -U icinga -d icinga < /usr/share/icinga2-ido-pgsql/schema/upgrade/<version>.sql

The Icinga 2 DB IDO module will check for the required database schema version on startup
and generate an error message if not satisfied.

**Example:** You are upgrading Icinga 2 from version `2.0.2` to `2.1.0`. Look into
the *upgrade* directory:

    $ ls /usr/share/icinga2-ido-pgsql/schema/upgrade/
    2.0.2.sql  2.1.0.sql

There is a new upgrade file called `2.1.0.sql` which must be applied to your IDO database.


#### <a id="installing-ido-postgresql"></a> Installing the IDO PostgreSQL module

The package provides a new configuration file that is installed in
`/etc/icinga2/features-available/ido-pgsql.conf`. You will need to update the
database credentials in this file.

You can enable the `ido-pgsql` feature configuration file using `icinga2-enable-feature`:

    # icinga2-enable-feature ido-pgsql
    Module 'ido-pgsql' was enabled.
    Make sure to restart Icinga 2 for these changes to take effect.

After enabling the ido-pgsql feature you have to restart Icinga 2:

Debian/Ubuntu, RHEL/CentOS 6 and SUSE:

    # service icinga2 restart

RHEL/CentOS 7 and Fedora 20:

    # systemctl restart icinga2.service


### <a id="setting-up-external-command-pipe"></a> Setting Up External Command Pipe

Web interfaces and other Icinga addons are able to send commands to
Icinga 2 through the external command pipe.

You can enable the External Command Pipe using icinga2-enable-feature:

    # icinga2-enable-feature command

After that you will have to restart Icinga 2:

Debian/Ubuntu, RHEL/CentOS 6 and SUSE:

    # service icinga2 restart

RHEL/CentOS 7 and Fedora 20:

    # systemctl restart icinga2.service

By default the command pipe file is owned by the group `icingacmd` with read/write
permissions. Add your webserver's user to the group `icingacmd` to
enable sending commands to Icinga 2 through your web interface:

    # usermod -G -a icingacmd www-data

Debian packages use `nagios` as the default user and group name. Therefore change `icingacmd` to
`nagios`. The webserver's user is different between distributions as well.

Change "www-data" to the user you're using to run queries.

> **Note**
>
> Packages will do that automatically. Verify that by running `id <your-webserver-user>` and skip this
> step.

## <a id="setting-up-livestatus"></a> Setting up Livestatus

The [MK Livestatus](http://mathias-kettner.de/checkmk_livestatus.html) project
implements a query protocol that lets users query their Icinga instance for
status information. It can also be used to send commands.

> **Tip**
>
> Only install the Livestatus feature if your web interface or addon requires
> you to do so (for example, [Icinga Web 2](#setting-up-icingaweb2)).
> [Icinga Classic UI](#setting-up-icinga-classic-ui) and [Icinga Web](#setting-up-icinga-web)
> do not use Livestatus as backend.

The Livestatus component that is distributed as part of Icinga 2 is a
re-implementation of the Livestatus protocol which is compatible with MK
Livestatus.

Details on the available tables and attributes with Icinga 2 can be found
in the [Livestatus Schema](#schema-livestatus) section.

You can enable Livestatus using icinga2-enable-feature:

    # icinga2-enable-feature livestatus

After that you will have to restart Icinga 2:

Debian/Ubuntu, RHEL/CentOS 6 and SUSE:

    # service icinga2 restart

RHEL/CentOS 7 and Fedora 20:

    # systemctl restart icinga2.service

By default the Livestatus socket is available in `/var/run/icinga2/cmd/livestatus`.

In order for queries and commands to work you will need to add your query user
(e.g. your web server) to the `icingacmd` group:

    # usermod -a -G icingacmd www-data

The Debian packages use `nagios` as the user and group name. Make sure to change `icingacmd` to
`nagios` if you're using Debian.

Change "www-data" to the user you're using to run queries.

In order to use the historical tables provided by the livestatus feature (for example, the
`log` table) you need to have the `CompatLogger` feature enabled. By default these logs
are expected to be in `/var/log/icinga2/compat`. A different path can be set using the
`compat_log_path` configuration attribute.

    # icinga2-enable-feature compatlog

## <a id="setting-up-icinga2-user-interfaces"></a> Setting up Icinga 2 User Interfaces

Icinga 2 is compatible with Icinga 1.x user interfaces by providing additional
features required as backends.

Furthermore these interfaces can be used for the newly created `Icinga Web 2`
user interface.

Some interface features will only work in a limited manner due to
[compatibility reasons](#differences-1x-2), other features like the
statusmap parents are available by dumping the host dependencies as parents.
Special restrictions are noted specifically in the sections below.

> **Tip**
>
> Choose your preferred interface. There's no need to install [Classic UI](#setting-up-icinga-classic-ui)
> if you prefer [Icinga Web](#setting-up-icinga-web) or [Icinga Web 2](#setting-up-icingaweb2) for example.

### <a id="icinga2-user-interface-requirements"></a> Requirements

* Web server (Apache2/Httpd, Nginx, Lighttp, etc)
* User credentials
* Firewall ports (tcp/80)

The Debian, RHEL and SUSE packages for Icinga [Classic UI](#setting-up-icinga-classic-ui),
[Web](#setting-up-icinga-web) and [Icingaweb 2](#setting-up-icingaweb2) depend on Apache2
as web server.

#### <a id="icinga2-user-interface-webserver"></a> Webserver

Debian/Ubuntu packages will automatically fetch and install the required packages.

RHEL/CentOS/Fedora:

    # yum install httpd
    # chkconfig httpd on && service httpd start
    ## RHEL7
    # systemctl enable httpd && systemctl start httpd

SUSE:

    # zypper install apache2
    # chkconfig on && service apache2 start

#### <a id="icinga2-user-interface-firewall-rules"></a> Firewall Rules

Example:

    # iptables -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
    # service iptables save

RHEL/CentOS 7 specific:

    # firewall-cmd --add-service=http
    # firewall-cmd --permanent --add-service=http

### <a id="setting-up-icinga-classic-ui"></a> Setting up Icinga Classic UI

Icinga 2 can write `status.dat` and `objects.cache` files in the format that
is supported by the Icinga 1.x Classic UI. [External commands](#external-commands)
(a.k.a. the "command pipe") are also supported. It also supports writing Icinga 1.x
log files which are required for the reporting functionality in the Classic UI.

#### <a id="installing-icinga-classic-ui"></a> Installing Icinga Classic UI

The Icinga package repository has both Debian and RPM packages. You can install
the Classic UI using the following packages:

  Distribution  | Packages
  --------------|---------------------
  Debian        | icinga2-classicui
  RHEL/SUSE     | icinga2-classicui-config icinga-gui

The Debian packages require additional packages which are provided by the
[Debian Monitoring Project](http://www.debmon.org) (`DebMon`) repository.

`libjs-jquery-ui` requires at least version `1.10.*` which is not available
in Debian Wheezy and Ubuntu 12.04 LTS (Precise). Add the following repositories
to satisfy this dependency:

  Distribution                  | Package Repositories
  ------------------------------|------------------------------
  Debian Wheezy                 | [wheezy-backports](http://backports.debian.org/Instructions/) or [DebMon](http://www.debmon.org)
  Ubuntu 12.04 LTS (Precise)    | [Icinga PPA](https://launchpad.net/~formorer/+archive/icinga)

On all distributions other than Debian you may have to restart both your web
server as well as Icinga 2 after installing the Classic UI package.

Icinga Classic UI requires the [StatusDataWriter](#status-data), [CompatLogger](#compat-logging)
and [ExternalCommandListener](#external-commands) features.
Enable these features and restart Icinga 2.

    # icinga2-enable-feature statusdata compatlog command

In order for commands to work you will need to [setup the external command pipe](#setting-up-external-command-pipe).

#### <a id="setting-up-icinga-classic-ui-summary"></a> Setting Up Icinga Classic UI Summary

Verify that your Icinga 1.x Classic UI works by browsing to your Classic
UI installation URL:

  Distribution  | URL                                                                      | Default Login
  --------------|--------------------------------------------------------------------------|--------------------------
  Debian        | [http://localhost/icinga2-classicui](http://localhost/icinga2-classicui) | asked during installation
  all others    | [http://localhost/icinga](http://localhost/icinga)                       | icingaadmin/icingaadmin

For further information on configuration, troubleshooting and interface documentation
please check the official [Icinga 1.x user interface documentation](http://docs.icinga.org/latest/en/ch06.html).

### <a id="setting-up-icinga-web"></a> Setting up Icinga Web

Icinga 2 can write to the same schema supplied by `Icinga IDOUtils 1.x` which
is an explicit requirement to run `Icinga Web` next to the external command pipe.
Therefore you need to setup the [DB IDO feature](#configuring-ido) remarked in the previous sections.

#### <a id="installing-icinga-web"></a> Installing Icinga Web

The Icinga package repository has both Debian and RPM packages. You can install
Icinga Web using the following packages (RPMs ship an additional configuration package):

  Distribution  | Packages
  --------------|-------------------------------------------------------
  RHEL/SUSE     | icinga-web icinga-web-{mysql,pgsql}
  Debian        | icinga-web icinga-web-config-icinga2-ido-{mysql,pgsql}

#### <a id="icinga-web-rpm-notes"></a> Icinga Web on RPM based systems

Additionally you need to setup the `icinga_web` database and import the database schema.
Details can be found in the package `README` files, for example [README.RHEL](https://github.com/Icinga/icinga-web/blob/master/doc/README.RHEL)

The Icinga Web RPM packages install the schema files into
`/usr/share/doc/icinga-web-*/schema` (`*` means package version).
The Icinga Web dist tarball ships the schema files in `etc/schema`.

On SuSE-based distributions the schema files are installed in
`/usr/share/doc/packages/icinga-web/schema`.

Example for RHEL and MySQL:

    # mysql -u root -p

    mysql> CREATE DATABASE icinga_web;
           GRANT SELECT, INSERT, UPDATE, DELETE, DROP, CREATE VIEW, INDEX, EXECUTE ON icinga_web.* TO 'icinga_web'@'localhost' IDENTIFIED BY 'icinga_web';
           quit

    # mysql -u root -p icinga_web <  /usr/share/doc/icinga-web-<version>/schema/mysql.sql

Icinga Web requires the IDO feature as database backend using MySQL or PostgreSQL.
Enable that feature, e.g. for MySQL.

    # icinga2-enable-feature ido-mysql

If you've changed your default credentials you may either create a read-only user
or use the credentials defined in the IDO feature for Icinga Web backend configuration.
Edit `databases.xml` accordingly and clear the cache afterwards. Further details can be
found in the [Icinga Web documentation](http://docs.icinga.org/latest/en/icinga-web-config.html).

    # vim /etc/icinga-web/conf.d/databases.xml

    # icinga-web-clearcache

Additionally you need to enable the `command` feature for sending [external commands](#external-commands):

    # icinga2-enable-feature command

In order for commands to work you will need to [setup the external command pipe](#setting-up-external-command-pipe).

Then edit the Icinga Web configuration for sending commands in `/etc/icinga-web/conf.d/access.xml`
(RHEL) or `/etc/icinga-web/access.xml` (SUSE) setting the command pipe path
to the default used in Icinga 2. Make sure to clear the cache afterwards.

    # vim /etc/icinga-web/conf.d/access.xml

                <write>
                    <files>
                        <resource name="icinga_pipe">/var/run/icinga2/cmd/icinga2.cmd</resource>
                    </files>
                </write>

    # icinga-web-clearcache

> **Note**
>
> The path to the Icinga Web `clearcache` script may differ. Please check the
> [Icinga Web documentation](https://docs.icinga.org) for details.

#### <a id="icinga-web-debian-notes"></a> Icinga Web on Debian systems

Since Icinga Web 1.11.1-2 on Debian and Ubuntu, the IDO autoconfiguration has been moved to additional packages.

The package `icinga-web` no longer configures the IDO connection, you can use one of the config packages:

 - `icinga-web-config-icinga2-ido-mysql`
 - `icinga-web-config-icinga2-ido-pgsql`

These packages take care of setup up the IDO connection, enabling the command pipe from Icinga Web
and depend on the corresponding packages of Icinga 2.

Please read the README.Debian files for details and how to do advanced configuration:

 - `/usr/share/doc/icinga-web/README.Debian`
 - `/usr/share/doc/icinga-web-config-icinga2-ido-mysql/README.Debian`
 - `/usr/share/doc/icinga-web-config-icinga2-ido-pgsql/README.Debian`

If you change the XML configuration of Icinga Web, make sure to clear the config cache:

    # /usr/lib/icinga-web/bin/clearcache.sh

> **Note**
>
> When you use an older version of icinga-web you should install it with:
> `apt-get install --no-install-recommends icinga-web`

#### <a id="setting-up-icinga-web-summary"></a> Setting Up Icinga Web Summary

Verify that your Icinga 1.x Web works by browsing to your Web installation URL:

  Distribution  | URL                                                         | Default Login
  --------------|-------------------------------------------------------------|--------------------------
  Debian        | [http://localhost/icinga-web](http://localhost/icinga-web)  | asked during installation
  all others    | [http://localhost/icinga-web](http://localhost/icinga-web)  | root/password

For further information on configuration, troubleshooting and interface documentation
please check the official [Icinga 1.x user interface documentation](http://docs.icinga.org/latest/en/ch06.html).


### <a id="setting-up-icingaweb2"></a> Setting up Icinga Web 2

Icinga Web 2 will support `status.dat`, `DB IDO`, or `Livestatus` as backends.

Using DB IDO as backend, you need to install and configure the [DB IDO backend](#configuring-db-ido).
Once finished, you can enable the feature for DB IDO MySQL:

    # icinga2-enable-feature ido-mysql

Furthermore [external commands](#external-commands) are supported through the external
command pipe.

    # icinga2-enable-feature command

In order for commands to work you will need to [setup the external command pipe](#setting-up-external-command-pipe).

Please consult the INSTALL documentation shipped with `Icinga Web 2` for
further instructions on how to install Icinga Web 2 and to configure
backends, resources and instances.

> **Note**
>
> Icinga Web 2 is still under heavy development. Rather than installing it
> yourself you should consider testing it using the available Vagrant
> demo VM in the [git repository](https://github.com/icinga/icingaweb2).

Check the [Icinga website](https://www.icinga.org) for release schedules,
blog updates and more.


### <a id="additional-visualization"></a> Additional visualization

There are many visualization addons which can be used with Icinga 2.

Some of the more popular ones are [PNP](#addons-graphing-pnp), [inGraph](#addons-graphing-pnp)
graphing performance data), [Graphite](#addons-graphing-pnp), and
[NagVis](#addons-visualization-nagvis) (network maps).


## <a id="configuration-tools"></a> Configuration Tools

If you require your favourite configuration tool to export Icinga 2 configuration, please get in
touch with their developers. The Icinga project does not provide a configuration web interface
or similar.

> **Tip**
>
> Get to know the new configuration format and the advanced [apply](#using-apply) rules and
> use [syntax highlighting](#configuration-syntax-highlighting) in vim/nano.

If you're looking for puppet manifests, chef cookbooks, ansible recipes, etc - we're happy
to integrate them upstream, so please get in touch at [https://support.icinga.org](https://support.icinga.org).

These tools are in development and require feedback and tests:

* [Ansible Roles](https://github.com/Icinga/icinga2-ansible)
* [Puppet Module](https://github.com/Icinga/puppet-icinga2)

## <a id="configuration-syntax-highlighting"></a> Configuration Syntax Highlighting

Icinga 2 ships configuration examples for syntax highlighting using the `vim` and `nano`editors.
The RHEL, SUSE and Debian package `icinga2-common` install these files into
`/usr/share/*/icinga2-common/syntax`. Sources provide these files in `tools/syntax`.

### <a id="configuration-syntax-highlighting-vim"></a> Configuration Syntax Highlighting using Vim

Create a new local vim configuration storage, if not already existing.
Edit `vim/ftdetect/icinga2.vim` if your paths to the Icinga 2 configuration
differ.

    $ PREFIX=~/.vim
    $ mkdir -p $PREFIX/{syntax,ftdetect}
    $ cp vim/syntax/icinga2.vim $PREFIX/syntax/
    $ cp vim/ftdetect/icinga2.vim $PREFIX/ftdetect/

Test it:

    $ vim /etc/icinga2/conf.d/templates.conf

### <a id="configuration-syntax-highlighting-nano"></a> Configuration Syntax Highlighting using Nano

Copy the `/etc/nanorc` sample file to your home directory. Create the `/etc/nano` directory
and copy the provided `icinga2.nanorc` into it.

    $ cp /etc/nanorc ~/.nanorc

    # mkdir -p /etc/nano
    # cp icinga2.nanorc /etc/nano/

Then include the icinga2.nanorc file in your ~/.nanorc by adding the following line:

    $ vim ~/.nanorc

    ## Icinga 2
    include "/etc/nano/icinga2.nanorc"

Test it:

    $ nano /etc/icinga2/conf.d/templates.conf


## <a id="running-icinga2"></a> Running Icinga 2

### <a id="init-script"></a> Init Script

Icinga 2's init script is installed in `/etc/init.d/icinga2` by default:

    # /etc/init.d/icinga2
    Usage: /etc/init.d/icinga2 {start|stop|restart|reload|checkconfig|status}

  Command             | Description
  --------------------|------------------------
  start               | The `start` action starts the Icinga 2 daemon.
  stop                | The `stop` action stops the Icinga 2 daemon.
  restart             | The `restart` action is a shortcut for running the `stop` action followed by `start`.
  reload              | The `reload` action sends the `HUP` signal to Icinga 2 which causes it to restart. Unlike the `restart` action `reload` does not wait until Icinga 2 has restarted.
  checkconfig         | The `checkconfig` action checks if the `/etc/icinga2/icinga2.conf` configuration file contains any errors.
  status              | The `status` action checks if Icinga 2 is running.

By default the Icinga 2 daemon is running as `icinga` user and group
using the init script. Using Debian packages the user and group are set to `nagios`
for historical reasons.

### <a id="systemd-service"></a> Systemd Service

Modern distributions (Fedora, OpenSUSE, etc.) already use `Systemd` natively. Enterprise-grade
distributions such as RHEL7 changed to `Systemd` recently. Icinga 2 Packages will install the
service automatically.

The Icinga 2 `Systemd` service can be (re)started, reloaded, stopped and also queried for its current status.

    # systemctl status icinga2
    icinga2.service - Icinga host/service/network monitoring system
       Loaded: loaded (/usr/lib/systemd/system/icinga2.service; disabled)
       Active: active (running) since Mi 2014-07-23 13:39:38 CEST; 15s ago
      Process: 21692 ExecStart=/usr/sbin/icinga2 -c ${ICINGA2_CONFIG_FILE} -d -e ${ICINGA2_ERROR_LOG} -u ${ICINGA2_USER} -g ${ICINGA2_GROUP} (code=exited, status=0/SUCCESS)
      Process: 21674 ExecStartPre=/usr/sbin/icinga2-prepare-dirs /etc/sysconfig/icinga2 (code=exited, status=0/SUCCESS)
     Main PID: 21727 (icinga2)
       CGroup: /system.slice/icinga2.service
               └─21727 /usr/sbin/icinga2 -c /etc/icinga2/icinga2.conf -d -e /var/log/icinga2/error.log -u icinga -g icinga --no-stack-rlimit

    Jul 23 13:39:38 nbmif icinga2[21692]: [2014-07-23 13:39:38 +0200] information/ConfigItem: Checked 309 Service(s).
    Jul 23 13:39:38 nbmif icinga2[21692]: [2014-07-23 13:39:38 +0200] information/ConfigItem: Checked 1 User(s).
    Jul 23 13:39:38 nbmif icinga2[21692]: [2014-07-23 13:39:38 +0200] information/ConfigItem: Checked 15 Notification(s).
    Jul 23 13:39:38 nbmif icinga2[21692]: [2014-07-23 13:39:38 +0200] information/ConfigItem: Checked 4 ScheduledDowntime(s).
    Jul 23 13:39:38 nbmif icinga2[21692]: [2014-07-23 13:39:38 +0200] information/ConfigItem: Checked 1 UserGroup(s).
    Jul 23 13:39:38 nbmif icinga2[21692]: [2014-07-23 13:39:38 +0200] information/ConfigItem: Checked 1 IcingaApplication(s).
    Jul 23 13:39:38 nbmif icinga2[21692]: [2014-07-23 13:39:38 +0200] information/ConfigItem: Checked 8 Dependency(s).
    Jul 23 13:39:38 nbmif systemd[1]: Started Icinga host/service/network monitoring system.

`Systemd` supports the following command actions:

  Command             | Description
  --------------------|------------------------
  start               | The `start` action starts the Icinga 2 daemon.
  stop                | The `stop` action stops the Icinga 2 daemon.
  restart             | The `restart` action is a shortcut for running the `stop` action followed by `start`.
  reload              | The `reload` action sends the `HUP` signal to Icinga 2 which causes it to restart. Unlike the `restart` action `reload` does not wait until Icinga 2 has restarted.
  status              | The `status` action checks if Icinga 2 is running.
  enable              | The `enable` action enables the service being started at system boot time (similar to `chkconfig`)

If you're stuck with configuration errors, you can manually invoke the [configuration validation](#config-validation).

    # systemctl enable icinga2

    # systemctl restart icinga2
    Job for icinga2.service failed. See 'systemctl status icinga2.service' and 'journalctl -xn' for details.

### <a id="cmdline"></a> Command-line Options

    $ icinga2 --help
    icinga2 - The Icinga 2 network monitoring daemon.

    Supported options:
      --help                show this help message
      -V [ --version ]      show version information
      -l [ --library ] arg  load a library
      -I [ --include ] arg  add include search directory
      -D [ --define] args   define a constant
      -c [ --config ] arg   parse a configuration file
      -C [ --validate ]     exit after validating the configuration
      -x [ --debug ] arg    enable debugging with severity level specified
      -d [ --daemonize ]    detach from the controlling terminal
      -e [ --errorlog ] arg log fatal errors to the specified log file (only works
                            in combination with --daemonize)
      -u [ --user ] arg     user to run Icinga as
      -g [ --group ] arg    group to run Icinga as

    Report bugs at <https://dev.icinga.org/>
    Icinga home page: <http://www.icinga.org/>

#### Libraries

Instead of loading libraries using the [`library` config directive](#library)
you can also use the `--library` command-line option.

#### Constants

[Global constants](#global-constants) can be set using the `--define` command-line option.

#### Config Include Path

When including files you can specify that the include search path should be
checked. You can do this by putting your configuration file name in angle
brackets like this:

    include <test.conf>

This would cause Icinga 2 to search its include path for the configuration file
`test.conf`. By default the installation path for the Icinga Template Library
is the only search directory.

Using the `--include` command-line option additional search directories can be
added.

#### Config Files

Using the `--config` option you can specify one or more configuration files.
Config files are processed in the order they're specified on the command-line.

When no configuration file is specified and the `--no-config` is not used
Icinga 2 automatically falls back to using the configuration file
`SysconfDir + "/icinga2/icinga2.conf"` (where SysconfDir is usually `/etc`).

#### Config Validation

The `--validate` option can be used to check if your configuration files
contain errors. If any errors are found the exit status is 1, otherwise 0
is returned.

### <a id="features"></a> Enabling/Disabling Features

Icinga 2 provides configuration files for some commonly used features. These
are installed in the `/etc/icinga2/features-available` directory and can be
enabled and disabled using the `icinga2-enable-feature` and `icinga2-disable-feature` tools,
respectively.

The `icinga2-enable-feature` tool creates symlinks in the `/etc/icinga2/features-enabled`
directory which is included by default in the example configuration file.

You can view a list of available feature configuration files:

    # icinga2-enable-feature
    Syntax: icinga2-enable-feature <feature>
    Enables the specified feature.

    Available features: statusdata

Using the `icinga2-enable-feature` command you can enable features:

    # icinga2-enable-feature statusdata
    Module 'statusdata' was enabled.
    Make sure to restart Icinga 2 for these changes to take effect.

You can disable features using the `icinga2-disable-feature` command:

    # icinga2-disable-feature statusdata
    Module 'statusdata' was disabled.
    Make sure to restart Icinga 2 for these changes to take effect.

The `icinga2-enable-feature` and `icinga2-disable-feature` commands do not
restart Icinga 2. You will need to restart Icinga 2 using the init script
after enabling or disabling features.

### <a id="config-validation"></a> Configuration Validation

Once you've edited the configuration files make sure to tell Icinga 2 to validate
the configuration changes. Icinga 2 will log any configuration error including
a hint on the file, the line number and the affected configuration line itself.

The following example creates an apply rule without any `assign` condition.

    apply Service "5872-ping4" {
      import "test-generic-service"
      check_command = "ping4"
      //assign where match("5872-*", host.name)
    }

Validate the configuration with the init script option `checkconfig`

    # /etc/init.d/icinga2 checkconfig

or manually passing the `-C` argument:

    # /usr/sbin/icinga2 -c /etc/icinga2/icinga2.conf -C

    [2014-05-22 17:07:25 +0200] critical/ConfigItem: Location:
    /etc/icinga2/conf.d/tests/5872.conf(5): }
    /etc/icinga2/conf.d/tests/5872.conf(6):
    /etc/icinga2/conf.d/tests/5872.conf(7): apply Service "5872-ping4" {
                                            ^^^^^^^^^^^^^
    /etc/icinga2/conf.d/tests/5872.conf(8):   import "test-generic-service"
    /etc/icinga2/conf.d/tests/5872.conf(9):   check_command = "ping4"

    Config error: 'apply' is missing 'assign'
    [2014-05-22 17:07:25 +0200] critical/ConfigItem: 1 errors, 0 warnings.
    Icinga 2 detected configuration errors.


### <a id="config-change-reload"></a> Reload on Configuration Changes

Everytime you have changed your configuration you should first tell  Icinga 2
to [validate](#config-validation). If there are no validation errors you can
safely reload the Icinga 2 daemon.

    # /etc/init.d/icinga2 reload

> **Note**
>
> The `reload` action will send the `SIGHUP` signal to the Icinga 2 daemon
> which will validate the configuration in a separate process and not stop
> the other events like check execution, notifications, etc.
>
> Details can be found [here](#differences-1x-2-real-reload).


## <a id="vagrant"></a> Vagrant Demo VM

The Icinga Vagrant Git repository contains support for [Vagrant](http://docs.vagrantup.com/v2/)
with VirtualBox. Please note that Vagrant version `1.0.x` is not supported. At least
version `1.2.x` is required.

In order to build the Vagrant VM first you will have to check out
the Git repository:

    $ git clone git://git.icinga.org/icinga-vagrant.git

For Icinga 2 there are currently two scenarios available:

* `icinga2x` bringing up a standalone box with Icinga 2
* `icinga2x-cluster` setting up two virtual machines in a master/slave cluster

> **Note**
>
> Please consult the `README.md` file for each project for further installation
> details at [https://github.com/Icinga/icinga-vagrant]

Once you have checked out the Git repository navigate to your required
vagrant box and build the VM using the following command:

    $ vagrant up

The Vagrant VMs are based on CentOS 6.x and are using the official
Icinga 2 RPM snapshot packages from `packages.icinga.org`. The check
plugins are installed from EPEL providing RPMs with sources from the
Monitoring Plugins project.