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

This tutorial is a step-by-step introduction to installing [Icinga 2](02-getting-started.md#setting-up-icinga2)
and [Icinga Web 2](02-getting-started.md#setting-up-icingaweb2).
It assumes that you are familiar with the operating system you're using to install Icinga 2.

In case you are upgrading an existing setup, please ensure to
follow the [upgrade documentation](16-upgrading-icinga-2.md#upgrading-icinga-2).

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

First off you 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                  | [Icinga Repository](https://packages.icinga.com/debian/)
  Ubuntu                  | [Icinga Repository](https://packages.icinga.com/ubuntu/)
  RHEL/CentOS             | [Icinga Repository](https://packages.icinga.com/epel/)
  openSUSE                | [Icinga Repository](https://packages.icinga.com/openSUSE/)
  SLES                    | [Icinga Repository](https://packages.icinga.com/SUSE/)
  Gentoo                  | [Upstream](https://packages.gentoo.org/package/net-analyzer/icinga2)
  FreeBSD                 | [Upstream](https://www.freshports.org/net-mgmt/icinga2)
  OpenBSD                 | [Upstream](http://ports.su/net/icinga/core2,-main)
  ArchLinux               | [Upstream](https://aur.archlinux.org/packages/icinga2)
  Alpine Linux            | [Upstream](https://pkgs.alpinelinux.org/package/edge/community/x86_64/icinga2)

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

### Package Repositories <a id="package-repositories"></a>

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

Debian:

    # wget -O - https://packages.icinga.com/icinga.key | apt-key add -
    # echo 'deb https://packages.icinga.com/debian icinga-stretch main' >/etc/apt/sources.list.d/icinga.list
    # apt-get update

Ubuntu:

    # wget -O - https://packages.icinga.com/icinga.key | apt-key add -
    # echo 'deb https://packages.icinga.com/ubuntu icinga-xenial main' >/etc/apt/sources.list.d/icinga.list
    # apt-get update

RHEL/CentOS 7:

    yum install https://packages.icinga.com/epel/icinga-rpm-release-7-latest.noarch.rpm

RHEL/CentOS 6:

    yum install https://packages.icinga.com/epel/icinga-rpm-release-6-latest.noarch.rpm

Fedora 26:

    dnf install https://packages.icinga.com/fedora/icinga-rpm-release-26-latest.noarch.rpm

Fedora 25:

    dnf install https://packages.icinga.com/fedora/icinga-rpm-release-25-latest.noarch.rpm

SLES 11:

    # zypper ar https://packages.icinga.com/SUSE/ICINGA-release-11.repo
    # zypper ref

SLES 12:

    # zypper ar https://packages.icinga.com/SUSE/ICINGA-release.repo
    # zypper ref

openSUSE:

    # zypper ar https://packages.icinga.com/openSUSE/ICINGA-release.repo
    # zypper ref


Alpine Linux:

    # echo "http://dl-cdn.alpinelinux.org/alpine/edge/community" >> /etc/apk/repositories
    # apk update

#### RHEL/CentOS EPEL Repository <a id="package-repositories-rhel-epel"></a>

The packages for RHEL/CentOS depend on other packages which are distributed
as part of the [EPEL repository](https://fedoraproject.org/wiki/EPEL).

CentOS 7/6:

    yum install epel-release

If you are using RHEL you need to enable the `optional` repository and then install
the [EPEL rpm package](https://fedoraproject.org/wiki/EPEL#How_can_I_use_these_extra_packages.3F).

#### SLES Security Repository <a id="package-repositories-sles-security"></a>

The packages for SLES 11 depend on the `openssl1` package which is distributed
as part of the [SLES 11 Security Module](https://www.suse.com/communities/conversations/introducing-the-suse-linux-enterprise-11-security-module/).

#### SLES 12 SDK <a id="package-sles-sdk"></a>

Icinga 2 requires the `libboost_chrono1_54_0` package from the `SLES 12 SDK` repository. Refer to the SUSE Enterprise
Linux documentation for further information.

#### Alpine Linux Notes  <a id="package-repositories-alpine-notes"></a>

The example provided assumes that you are running Alpine edge, which is the -dev branch and is a rolling release.
If you are using a stable version please "pin" the edge repository on the latest Icinga 2 package version.
In order to correctly manage your repository, please follow
[these instructions](https://wiki.alpinelinux.org/wiki/Alpine_Linux_package_management)

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

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 6:

    # yum install icinga2
    # chkconfig icinga2 on
    # service icinga2 start

RHEL/CentOS 7 and Fedora:

    # yum install icinga2
    # systemctl enable icinga2
    # systemctl start icinga2

SLES/openSUSE:

    # zypper install icinga2

FreeBSD:

    # pkg install icinga2


Alpine Linux:

    # apk add icinga2

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

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

You can verify that by calling `icinga2 feature list`
[CLI command](11-cli-commands.md#cli-command-feature) to see which features are
enabled and disabled.

    # icinga2 feature list
    Disabled features: api command compatlog debuglog gelf graphite icingastatus ido-mysql ido-pgsql influxdb livestatus opentsdb perfdata statusdata syslog
    Enabled features: checker mainlog notification


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

By default Icinga 2 uses the following files and directories:

  Path                                		| Description
  ----------------------------------------------|------------------------------------
  /etc/icinga2                        		| Contains Icinga 2 configuration files.
  /usr/lib/systemd/system/icinga2.service 	| The Icinga 2 Systemd service file on systems using Systemd.
  /etc/systemd/system/icinga2.service.d/limits.conf | On distributions with Systemd >227, additional service limits are required.
  /etc/init.d/icinga2                 		| The Icinga 2 init script on systems using SysVinit or OpenRC.
  /usr/sbin/icinga2                   		| Shell wrapper for the Icinga 2 binary.
  /usr/lib\*/icinga2				| Libraries and the Icinga 2 binary (use `find /usr -type f -name icinga2` to locate the binary path).
  /usr/share/doc/icinga2              		| Documentation files that come with Icinga 2.
  /usr/local/share/icinga2/include          		| The Icinga Template Library and plugin command configuration.
  /var/lib/icinga2                    		| Icinga 2 state file, cluster log, master CA, node certificates and configuration files (cluster, api).
  /var/run/icinga2                    		| PID file.
  /var/run/icinga2/cmd                		| Command pipe and Livestatus socket.
  /var/cache/icinga2                  		| status.dat/objects.cache, icinga2.debug files.
  /var/spool/icinga2                  		| Used for performance data spool files.
  /var/log/icinga2                    		| Log file location and compat/ directory for the CompatLogger feature.

FreeBSD uses slightly different paths:

By default Icinga 2 uses the following files and directories:

  Path                                | Description
  ------------------------------------|------------------------------------
  /usr/local/etc/icinga2              | Contains Icinga 2 configuration files.
  /usr/local/etc/rc.d/icinga2         | The Icinga 2 init script.
  /usr/local/sbin/icinga2             | Shell wrapper for the Icinga 2 binary.
  /usr/local/lib/icinga2              | Libraries and the Icinga 2 binary.
  /usr/local/share/doc/icinga2        | Documentation files that come with Icinga 2.
  /usr/local/share/icinga2/include    | The Icinga Template Library and plugin command configuration.
  /var/lib/icinga2                    | Icinga 2 state file, cluster log, master CA, node certificates and configuration files (cluster, api).
  /var/run/icinga2                    | PID file.
  /var/run/icinga2/cmd                | Command pipe and Livestatus socket.
  /var/cache/icinga2                  | status.dat/objects.cache, icinga2.debug files.
  /var/spool/icinga2                  | Used for performance data spool files.
  /var/log/icinga2                    | Log file location and compat/ directory for the CompatLogger feature.

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

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.

These plugins are required to make the [example configuration](04-configuring-icinga-2.md#configuring-icinga2-overview)
work out-of-the-box.

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

OS/Distribution        | Package Name       | Repository                | Installation Path
-----------------------|--------------------|---------------------------|----------------------------
RHEL/CentOS            | nagios-plugins-all | [EPEL](https://fedoraproject.org/wiki/EPEL) | /usr/lib/nagios/plugins or /usr/lib64/nagios/plugins
SLES/OpenSUSE          | monitoring-plugins | [server:monitoring](https://build.opensuse.org/project/repositories/server:monitoring) | /usr/lib/nagios/plugins
Debian/Ubuntu          | monitoring-plugins | -                         | /usr/lib/nagios/plugins
FreeBSD                | monitoring-plugins | -                         | /usr/local/libexec/nagios
Alpine Linux           | monitoring-plugins | -                         | /usr/lib/monitoring-plugins
OS X                   | nagios-plugins     | [MacPorts](https://www.macports.org), [Homebrew](https://brew.sh) | /opt/local/libexec or /usr/local/sbin

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

Debian/Ubuntu:

    # apt-get install monitoring-plugins

RHEL/CentOS:

    # yum install nagios-plugins-all

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

Fedora:

    # dnf install nagios-plugins-all

SLES/openSUSE:

    # zypper install monitoring-plugins

The packages for SLES/OpenSUSE depend on other packages which are distributed
as part of the [server:monitoring repository](https://build.opensuse.org/project/repositories/server:monitoring).
Please make sure to enable this repository beforehand.

FreeBSD:

    # pkg install monitoring-plugins

Alpine Linux:

    # apk add monitoring-plugins

Note: For Alpine you don't need to explicitly add the `monitoring-plugins` package since it is a dependency of
`icinga2` and is pulled automatically.

Depending on which directory your plugins are installed into you may need to
update the global `PluginDir` constant in your [Icinga 2 configuration](04-configuring-icinga-2.md#constants-conf).
This constant is used by the check command definitions contained in the Icinga Template Library
to determine where to find the plugin binaries.

> **Note**
>
> Please refer to the [service monitoring](05-service-monitoring.md#service-monitoring-plugins) chapter for details about how to integrate
> additional check plugins into your Icinga 2 setup.

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

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

Icinga 2's init script is installed in `/etc/init.d/icinga2` (`/usr/local/etc/rc.d/icinga2` on FreeBSD) by default:

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

The init script supports the following 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.
  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.

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

Some distributions (e.g. Fedora, openSUSE and RHEL/CentOS 7) use Systemd. The
Icinga 2 packages automatically install the necessary Systemd unit files.

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.

The `systemctl` command supports the following 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`)

Examples:

    # systemctl enable icinga2

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

If you're stuck with configuration errors, you can manually invoke the
[configuration validation](11-cli-commands.md#config-validation).

Usually Icinga 2 is a mission critical part of infrastructure and should be
online at all times. In case of a recoverable crash (e.g. OOM) you may want to
restart Icinga 2 automatically. With Systemd it is as easy as overriding some
settings of the Icinga 2 Systemd service by creating
`/etc/systemd/system/icinga2.service.d/override.conf` with the following
content:

    [Service]
    Restart=always
    RestartSec=1
    StartLimitInterval=10
    StartLimitBurst=3

Run `systemctl daemon-reload && systemctl restart icinga2` to apply the changes.
Now Systemd will always try to restart Icinga 2 (except if you run
`systemctl stop icinga2`). After three failures in ten seconds it will stop
trying because you probably have a problem that requires manual intervention.

> **Tip**
>
> If you are running into fork errors with Systemd enabled distributions,
> please check the [troubleshooting chapter](15-troubleshooting.md#check-fork-errors).

### FreeBSD <a id="running-icinga2-freebsd"></a>

On FreeBSD you need to enable icinga2 in your rc.conf

    # sysrc icinga2_enable=yes

    # service icinga2 restart


### SELinux <a id="running-icinga2-selinux"></a>

SELinux is a mandatory access control (MAC) system on Linux which adds
a fine-grained permission system for access to all system resources such
as files, devices, networks and inter-process communication.

Icinga 2 provides its own SELinux policy. `icinga2-selinux` is a policy package
for Red Hat Enterprise Linux 7 and derivatives. The package runs the targeted policy
which confines Icinga 2 including enabled features and running commands.

RHEL/CentOS 7:

```
yum install icinga2-selinux
```

Fedora:

```
dnf install icinga2-selinux
```

Read more about SELinux in [this chapter](22-selinux.md#selinux).

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

Icinga 2 ships configuration examples for syntax highlighting using the `vim` and `nano` editors.
The RHEL and SUSE package `icinga2-common` installs these files into `/usr/share/doc/icinga2-common-[x.x.x]/syntax`
(where `[x.x.x]` is the version number, e.g. `2.4.3` or `2.4.4`). Sources provide these files in `tools/syntax`.
On Debian systems the `icinga2-common` package provides only the Nano configuration file (`/usr/share/nano/icinga2.nanorc`);
to obtain the Vim configuration, please install the extra package `vim-icinga2`. The files are located in `/usr/share/vim/addons`.

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

Install the package `vim-icinga2` with your distribution's package manager.

Debian/Ubuntu:

    # apt-get install vim-icinga2 vim-addon-manager
    # vim-addon-manager -w install icinga2
    Info: installing removed addon 'icinga2' to /var/lib/vim/addons

RHEL/CentOS/Fedora:

    # yum install vim-icinga2

SLES/openSUSE:

    # zypper install vim-icinga2

Alpine Linux:

    # apk add icinga2-vim

Ensure that syntax highlighting is enabled e.g. by editing the user's `vimrc`
configuration file:

    # vim ~/.vimrc
    syntax on

Test it:

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

![Vim with syntax highlighting](images/getting-started/vim-syntax.png "Vim with Icinga 2 syntax highlighting")


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

Install the package `nano-icinga2` with your distribution's package manager.

Debian/Ubuntu:

**Note:** The syntax files are installed with the `icinga2-common` package already.

RHEL/CentOS/Fedora:

    # yum install nano-icinga2

SLES/openSUSE:

    # zypper install nano-icinga2

Copy the `/etc/nanorc` sample file to your home directory.

    $ cp /etc/nanorc ~/.nanorc

Include the `icinga2.nanorc` file.

    $ vim ~/.nanorc

    ## Icinga 2
    include "/usr/share/nano/icinga2.nanorc"

Test it:

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

![Nano with syntax highlighting](images/getting-started/nano-syntax.png "Nano with Icinga 2 syntax highlighting")

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

Icinga 2 can be used with Icinga Web 2 and a number of other web interfaces.
This chapter explains how to set up Icinga Web 2.

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 2](02-getting-started.md#setting-up-icingaweb2), Icinga Reporting
or Icinga Web 1.x.

There is a separate module for each database backend. At present support for
both MySQL and PostgreSQL has been implemented.

Please choose whether to install [MySQL](02-getting-started.md#configuring-db-ido-mysql) or
[PostgreSQL](02-getting-started.md#configuring-db-ido-postgresql).

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

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

Debian/Ubuntu:

    # apt-get install mysql-server mysql-client
    # mysql_secure_installation

RHEL/CentOS 6:

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

RHEL/CentOS 7 and Fedora:

    # yum install mariadb-server mariadb
    # systemctl enable mariadb
    # systemctl start mariadb
    # mysql_secure_installation

SUSE:

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

FreeBSD:

    # pkg install mysql56-server
    # sysrc mysql_enable=yes
    # service mysql-server restart
    # mysql_secure_installation

Alpine Linux:

    # apk add mariadb
    # rc-service mariadb setup
    # rc-update add mariadb default
    # rc-service mariadb start

#### Installing the IDO modules for MySQL <a id="installing-database-mysql-modules"></a>

The next step is 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

FreeBSD:

On FreeBSD the IDO modules for MySQL are included with the icinga2 package
and located at /usr/local/share/icinga2-ido-mysql/schema/mysql.sql

Alpine Linux:

On Alpine Linux the IDO modules for MySQL are included with the `icinga2` package
and located at /usr/local/share/icinga2-ido-mysql/schema/mysql.sql

> **Note**
>
> The Debian/Ubuntu 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 MySQL database <a id="setting-up-mysql-db"></a>

Set up a MySQL database for Icinga 2:

    # mysql -u root -p

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

![setting up the database on CentOS 7](images/getting-started/mariadb-centos7.png "Setting up the database on CentOS 7")

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

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


#### Enabling the IDO MySQL module <a id="enabling-ido-mysql"></a>

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.

All available attributes are explained in the
[IdoMysqlConnection object](09-object-types.md#objecttype-idomysqlconnection)
chapter.

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

    # icinga2 feature enable 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:

RHEL/CentOS 7/Fedora, SLES 12/openSUSE > 12.2, Debian Jessie/Stretch, Ubuntu Xenial:

    # systemctl restart icinga2

Debian/Ubuntu, RHEL/CentOS 6, SLES 11/openSUSE < 12.3 and FreeBSD:

    # service icinga2 restart

Alpine Linux:

   # rc-service icinga2 restart

Continue with the [webserver setup](02-getting-started.md#icinga2-user-interface-webserver).

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

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

Debian/Ubuntu:

    # apt-get install postgresql

RHEL/CentOS 6:

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

RHEL/CentOS 7:

    # yum install postgresql-server postgresql
    # postgresql-setup initdb
    # systemctl enable postgresql
    # systemctl start postgresql

SUSE:

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

FreeBSD:

    # pkg install postgresql93-server
    # sysrc postgresql_enable=yes
    # service postgresql initdb
    # service postgresql start

Alpine Linux:

    # apk add postgresql
    # rc-update add postgresql default
    # rc-service postgresql setup
    # rc-service postgresql start

#### Installing the IDO modules for PostgreSQL <a id="installing-database-postgresql-modules"></a>

The next step is 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

FreeBSD:

On FreeBSD the IDO modules for PostgreSQL are included with the icinga2 package
and located at /usr/local/share/icinga2-ido-pgsql/schema/pgsql.sql

Alpine Linux:

On Alpine Linux the IDO modules for PostgreSQL are included with the `icinga2` package
and located at /usr/local/share/icinga2-ido-pgsql/schema/pgsql.sql

> **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**
>
> When using PostgreSQL 9.x you can omit the `createlang` command.
> Also it is assumed here that your locale is set to utf-8, you may run into
> problems otherwise.

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.

    # 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

    # service 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/local/share/icinga2-ido-pgsql/schema/pgsql.sql

![importing the Icinga 2 IDO schema](images/getting-started/postgr-import-ido.png "Importing the Icinga 2 IDO schema on Debian Jessie")


#### Enabling the IDO PostgreSQL module <a id="enabling-ido-postgresql"></a>

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.

All available attributes are explained in the
[IdoPgsqlConnection object](09-object-types.md#objecttype-idopgsqlconnection)
chapter.

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

    # icinga2 feature enable 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:

RHEL/CentOS 7/Fedora, SLES 12/openSUSE > 12.2, Debian Jessie/Stretch, Ubuntu Xenial:

    # systemctl restart icinga2

Debian/Ubuntu, RHEL/CentOS 6, SLES 11/openSUSE < 12.3 and FreeBSD:

    # service icinga2 restart

Alpine Linux:

    # rc-service icinga2 restart

Continue with the [webserver setup](02-getting-started.md#icinga2-user-interface-webserver).

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

Debian/Ubuntu:

    # apt-get install apache2

RHEL/CentOS 6:

    # yum install httpd
    # chkconfig httpd on
    # service httpd start

RHEL/CentOS 7, Fedora:

    # yum install httpd
    # systemctl enable httpd
    # systemctl start httpd

SUSE:

    # zypper install apache2
    # chkconfig on
    # service apache2 start

FreeBSD (nginx, but you could also use the apache24 package):

    # pkg install nginx php56-gettext php56-ldap php56-openssl php56-mysql php56-pdo_mysql php56-pgsql php56-pdo_pgsql php56-sockets php56-gd pecl-imagick pecl-intl
    # sysrc php_fpm_enable=yes
    # sysrc nginx_enable=yes
    # sed -i '' "s/listen\ =\ 127.0.0.1:9000/listen\ =\ \/var\/run\/php5-fpm.sock/" /usr/local/etc/php-fpm.conf
    # sed -i '' "s/;listen.owner/listen.owner/" /usr/local/etc/php-fpm.conf
    # sed -i '' "s/;listen.group/listen.group/" /usr/local/etc/php-fpm.conf
    # sed -i '' "s/;listen.mode/listen.mode/" /usr/local/etc/php-fpm.conf
    # service php-fpm start
    # service nginx start

Alpine Linux:

    # apk add apache2 php7-apache2
    # sed -i -e "s/^#LoadModule rewrite_module/LoadModule rewrite_module/" /etc/apache2/httpd.conf
    # rc-update add apache2 default
    # rc-service apache2 start

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

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

FreeBSD:
Please consult the [FreeBSD Handbook](https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/firewalls.html) how to configure one of FreeBSD's firewalls.


### Setting Up Icinga 2 REST API <a id="setting-up-rest-api"></a>

Icinga Web 2 and other web interfaces require the [REST API](12-icinga2-api.md#icinga2-api-setup)
to send actions (reschedule check, etc.) and query object details.

You can run the CLI command `icinga2 api setup` to enable the
`api` [feature](11-cli-commands.md#enable-features) and set up
certificates as well as a new API user `root` with an auto-generated password in the
`/etc/icinga2/conf.d/api-users.conf` configuration file:

    # icinga2 api setup

Edit the `api-users.conf` file and add a new ApiUser object. Specify the [permissions](12-icinga2-api.md#icinga2-api-permissions)
attribute with minimal permissions required by Icinga Web 2.

    # vim /etc/icinga2/conf.d/api-users.conf

    object ApiUser "icingaweb2" {
      password = "Wijsn8Z9eRs5E25d"
      permissions = [ "status/query", "actions/*", "objects/modify/*", "objects/query/*" ]
    }

Make sure to restart Icinga 2 to activate the configuration.

RHEL/CentOS 7/Fedora, SLES 12/openSUSE > 12.2, Debian Jessie/Stretch, Ubuntu Xenial:

    # systemctl restart icinga2

Debian/Ubuntu, RHEL/CentOS 6, SLES 11/openSUSE < 12.3 and FreeBSD:

    # service icinga2 restart

Alpine Linux:

    # rc-service icinga2 restart

### Installing Icinga Web 2 <a id="installing-icingaweb2"></a>

Please consult the [installation documentation](https://www.icinga.com/docs/icingaweb2/latest/doc/02-Installation/)
for further instructions on how to install Icinga Web 2.

The Icinga 2 API can be defined as [command transport](https://www.icinga.com/docs/icingaweb2/latest/modules/monitoring/doc/05-Command-Transports/)
in Icinga Web 2 >= 2.4.

## Addons <a id="install-addons"></a>

A number of additional features are available in the form of addons. A list of
popular addons is available in the
[Addons and Plugins](13-addons.md#addons) chapter.

## Backup <a id="install-backup"></a>

Ensure to include the following in your backups:

* Configuration files in `/etc/icinga2`
* Certificate files in `/var/lib/icinga2/ca` (Master CA key pair) and `/var/lib/icinga2/certs` (node certificates)
* Runtime files in `/var/lib/icinga2`
* Optional: IDO database backup
