.. _installation-rhel:

==============================================================
RHEL / CentOS / Scientific Linux / Amazon Linux / Oracle Linux
==============================================================

.. _installation-rhel-repo:

Salt should work properly with all mainstream derivatives of Red Hat Enterprise
Linux, including CentOS, Scientific Linux, Oracle Linux, and Amazon Linux.
Report any bugs or issues on the `issue tracker`__.

.. __: https://github.com/saltstack/salt/issues

Installation from the SaltStack Repository
==========================================

2015.5 and later packages for RHEL 5, 6, and 7 are available in the
SaltStack repository.

.. important::
  The repository folder structure changed in the 2015.8.3 release, though the
  previous repository structure that was documented in 2015.8.1 can continue to
  be used.

To install using the SaltStack repository:

#. Run one of the following commands based on your version to import the SaltStack repository key:

   Version 7:

   .. code-block:: bash

       rpm --import https://repo.saltstack.com/yum/redhat/7/x86_64/latest/SALTSTACK-GPG-KEY.pub

   Version 6:

   .. code-block:: bash

       rpm --import https://repo.saltstack.com/yum/redhat/6/x86_64/latest/SALTSTACK-GPG-KEY.pub

   Version 5:

   .. code-block:: bash

       wget https://repo.saltstack.com/yum/redhat/5/x86_64/latest/SALTSTACK-EL5-GPG-KEY.pub
       rpm --import SALTSTACK-EL5-GPG-KEY.pub
       rm -f SALTSTACK-EL5-GPG-KEY.pub

#. Save the following file to ``/etc/yum.repos.d/saltstack.repo``:

   Version 7 and 6:

   .. code-block:: cfg

       [saltstack-repo]
       name=SaltStack repo for RHEL/CentOS $releasever
       baseurl=https://repo.saltstack.com/yum/redhat/$releasever/$basearch/latest
       enabled=1
       gpgcheck=1
       gpgkey=https://repo.saltstack.com/yum/redhat/$releasever/$basearch/latest/SALTSTACK-GPG-KEY.pub

   Version 5:

   .. code-block:: cfg

       [saltstack-repo]
       name=SaltStack repo for RHEL/CentOS $releasever
       baseurl=https://repo.saltstack.com/yum/redhat/$releasever/$basearch/latest
       enabled=1
       gpgcheck=1
       gpgkey=https://repo.saltstack.com/yum/redhat/$releasever/$basearch/latest/SALTSTACK-EL5-GPG-KEY.pub

#. Run ``sudo yum clean expire-cache``.

#. Run ``sudo yum update``.

#. Install the salt-minion, salt-master, or other Salt components:

   - ``yum install salt-master``
   - ``yum install salt-minion``
   - ``yum install salt-ssh``
   - ``yum install salt-syndic``
   - ``yum install salt-cloud``

.. note::
    EPEL support is not required when installing using the SaltStack repository
    on Red Hat 6 and 7. EPEL must be enabled when installing on Red Hat 5.

Post-installation tasks
=======================

**Master**

To have the Master start automatically at boot time:

.. code-block:: bash

    chkconfig salt-master on

To start the Master:

.. code-block:: bash

    service salt-master start

**Minion**

To have the Minion start automatically at boot time:

.. code-block:: bash

    chkconfig salt-minion on


To start the Minion:

.. code-block:: bash

    service salt-minion start

Now go to the :doc:`Configuring Salt</ref/configuration/index>` page.

Installation from the Community Repository
==========================================

Beginning with version 0.9.4, Salt has been available in `EPEL`_. For
RHEL/CentOS 5, `Fedora COPR`_ is recommended due to the removal of some
dependencies from EPEL5.

On RHEL/CentOS 6, the proper Jinja package 'python-jinja2' was moved from EPEL
to the "RHEL Server Optional Channel". Verify this repository is enabled before
installing salt on RHEL/CentOS 6.

.. note::
   Packages in these repositories are community built, and it can
   take a little while until the latest SaltStack release is available
   in this repository.

.. _`EPEL`: http://fedoraproject.org/wiki/EPEL
.. _`Fedora COPR`: https://copr.fedoraproject.org/coprs/saltstack/salt-el5/

RHEL/CentOS 6 and 7, Scientific Linux, etc.
-------------------------------------------

.. warning::
    Salt 2015.8 requires ``python-crypto`` 2.6.1 or higher, and ``python-tornado`` version
    4.2.1 or higher. These packages are not currently available in EPEL for
    Red Hat 5 and 6. You must install these dependencies from another location
    or use the SaltStack repository documented above.

Enabling EPEL
*************

If the EPEL repository is not installed on your system, you can download the
RPM for `RHEL/CentOS 6`_ or for `RHEL/CentOS 7`_ and install it
using the following command:

.. code-block:: bash

    rpm -Uvh epel-release-X-Y.rpm

Replace ``epel-release-X-Y.rpm`` with the appropriate filename.

.. _RHEL/CentOS 6: http://download.fedoraproject.org/pub/epel/6/i386/repoview/epel-release.html
.. _RHEL/CentOS 7: http://download.fedoraproject.org/pub/epel/7/x86_64/repoview/epel-release.html


Installing Stable Release
*************************

Salt is packaged separately for the minion and the master. It is necessary
to install only the appropriate package for the role the machine will play.
Typically, there will be one master and multiple minions.

   - ``yum install salt-master``
   - ``yum install salt-minion``
   - ``yum install salt-ssh``
   - ``yum install salt-syndic``
   - ``yum install salt-cloud``

Installing from ``epel-testing``
********************************

When a new Salt release is packaged, it is first admitted into the
``epel-testing`` repository, before being moved to the stable repo.

To install from ``epel-testing``, use the ``enablerepo`` argument for yum:

.. code-block:: bash

    yum --enablerepo=epel-testing install salt-minion

Installation Using pip
======================

Since Salt is on `PyPI`_, it can be installed using pip, though most users
prefer to install using RPMs (which can be installed from `EPEL`_).

Installing from pip has a few additional requirements:

* Install the group 'Development Tools', ``yum groupinstall 'Development Tools'``
* Install the 'zeromq-devel' package if it fails on linking against that
  afterwards as well.

A pip install does not make the init scripts or the /etc/salt directory, and you
will need to provide your own systemd service unit.

Installation from pip:

.. _`PyPI`: https://pypi.python.org/pypi/salt

.. code-block:: bash

    pip install salt

.. warning::

    If installing from pip (or from source using ``setup.py install``), be
    advised that the ``yum-utils`` package is needed for Salt to manage
    packages. Also, if the Python dependencies are not already installed, then
    you will need additional libraries/tools installed to build some of them.
    More information on this can be found :ref:`here
    <installing-for-development>`.

ZeroMQ 4
========

We recommend using ZeroMQ 4 where available. SaltStack provides ZeroMQ 4.0.4
and pyzmq 14.3.1 in the :ref:`SaltStack Repository <installation-rhel-repo>`
as well as a COPR_ repository.

.. _COPR: http://copr.fedoraproject.org/coprs/saltstack/zeromq4/

If this repo is added *before* Salt is installed, then installing either
``salt-master`` or ``salt-minion`` will automatically pull in ZeroMQ 4.0.4, and
additional states to upgrade ZeroMQ and pyzmq are unnecessary.

.. warning:: RHEL/CentOS 5 Users
    Using COPR repos on RHEL/CentOS 5 requires that the ``python-hashlib``
    package be installed. Not having it present will result in checksum errors
    because YUM will not be able to process the SHA256 checksums used by COPR.

.. note::
    For RHEL/CentOS 5 installations, if using the new repository to install
    Salt (as detailed :ref:`above <installation-rhel-5>`), then it is not
    necessary to enable the zeromq4 COPR, as the new EL5 repository includes
    ZeroMQ 4.


Package Management
==================

Salt's interface to :mod:`yum <salt.modules.yumpkg>` makes heavy use of the
**repoquery** utility, from the yum-utils_ package. This package will be
installed as a dependency if salt is installed via EPEL. However, if salt has
been installed using pip, or a host is being managed using salt-ssh, then as of
version 2014.7.0 yum-utils_ will be installed automatically to satisfy this
dependency.

.. _yum-utils: http://yum.baseurl.org/wiki/YumUtils

Post-installation tasks
=======================

**Master**

To have the Master start automatically at boot time:

.. code-block:: bash

    chkconfig salt-master on


To start the Master:

.. code-block:: bash

    service salt-master start

**Minion**

To have the Minion start automatically at boot time:

.. code-block:: bash

    chkconfig salt-minion on


To start the Minion:

.. code-block:: bash

    service salt-minion start

Now go to the :doc:`Configuring Salt</ref/configuration/index>` page.
