.. _salt-ssh:

========
Salt SSH
========

.. raw:: html
 :file: index.html

Getting Started
===============

Salt SSH is very easy to use, simply set up a basic :ref:`roster <ssh-roster>` file of the
systems to connect to and run ``salt-ssh`` commands in a similar way as
standard ``salt`` commands.

- Salt ssh is considered production ready in version 2014.7.0
- Python is required on the remote system (unless using the ``-r`` option to send raw ssh commands)
- On many systems, the ``salt-ssh`` executable will be in its own package, usually named
  ``salt-ssh``
- The Salt SSH system does not supercede the standard Salt communication
  systems, it simply offers an SSH-based alternative that does not require
  ZeroMQ and a remote agent. Be aware that since all communication with Salt SSH is
  executed via SSH it is substantially slower than standard Salt with ZeroMQ.
- At the moment fileserver operations must be wrapped to ensure that the
  relevant files are delivered with the ``salt-ssh`` commands.
  The state module is an exception, which compiles the state run on the
  master, and in the process finds all the references to ``salt://`` paths and
  copies those files down in the same tarball as the state run.
  However, needed fileserver wrappers are still under development.

Salt SSH Roster
===============

The roster system in Salt allows for remote minions to be easily defined.

.. note::
    See the :ref:`SSH roster docs <ssh-roster>` for more details.

Simply create the roster file, the default location is `/etc/salt/roster`:

.. code-block:: yaml

    web1: 192.168.42.1

This is a very basic roster file where a Salt ID is being assigned to an IP
address. A more elaborate roster can be created:

.. code-block:: yaml

    web1:
      host: 192.168.42.1 # The IP addr or DNS hostname
      user: fred         # Remote executions will be executed as user fred
      passwd: foobarbaz  # The password to use for login, if omitted, keys are used
      sudo: True         # Whether to sudo to root, not enabled by default
    web2:
      host: 192.168.42.2

.. note::
    sudo works only if NOPASSWD is set for user in /etc/sudoers:
    ``fred ALL=(ALL) NOPASSWD: ALL``

Deploy ssh key for salt-ssh
===========================

By default, salt-ssh will generate key pairs for ssh, the default path will be
/etc/salt/pki/master/ssh/salt-ssh.rsa

You can use ssh-copy-id, (the OpenSSH key deployment tool) to deploy keys to your servers.

.. code-block:: bash

   ssh-copy-id -i /etc/salt/pki/master/ssh/salt-ssh.rsa.pub user@server.demo.com

One could also create a simple shell script, named salt-ssh-copy-id.sh as follows:

.. code-block:: bash

   #!/bin/bash
   if [ -z $1 ]; then
      echo $0 user@host.com
      exit 0
   fi
   ssh-copy-id -i /etc/salt/pki/master/ssh/salt-ssh.rsa.pub $1


.. note::
    Be certain to chmod +x salt-ssh-copy-id.sh.

.. code-block:: bash

   ./salt-ssh-copy-id.sh user@server1.host.com
   ./salt-ssh-copy-id.sh user@server2.host.com

Once keys are successfully deployed, salt-ssh can be used to control them.


Calling Salt SSH
================

.. note:: ``salt-ssh`` on RHEL/CentOS 5

    The ``salt-ssh`` command requires at least python 2.6, which is not
    installed by default on RHEL/CentOS 5.  An easy workaround in this
    situation is to use the ``-r`` option to run a raw shell command that
    installs python26:

    .. code-block:: bash

        salt-ssh centos-5-minion -r 'yum -y install epel-release ; yum -y install python26'

The ``salt-ssh`` command can be easily executed in the same way as a salt
command:

.. code-block:: bash

    salt-ssh '*' test.ping

Commands with ``salt-ssh`` follow the same syntax as the ``salt`` command.

The standard salt functions are available! The output is the same as ``salt``
and many of the same flags are available. Please see
http://docs.saltstack.com/ref/cli/salt-ssh.html for all of the available
options.

Raw Shell Calls
---------------

By default ``salt-ssh`` runs Salt execution modules on the remote system,
but ``salt-ssh`` can also execute raw shell commands:

.. code-block:: bash

    salt-ssh '*' -r 'ifconfig'

States Via Salt SSH
===================

The Salt State system can also be used with ``salt-ssh``. The state system
abstracts the same interface to the user in ``salt-ssh`` as it does when using
standard ``salt``. The intent is that Salt Formulas defined for standard
``salt`` will work seamlessly with ``salt-ssh`` and vice-versa.

The standard Salt States walkthroughs function by simply replacing ``salt``
commands with ``salt-ssh``.

Targeting with Salt SSH
=======================

Due to the fact that the targeting approach differs in salt-ssh, only glob
and regex targets are supported as of this writing, the remaining target
systems still need to be implemented.

.. note::
    By default, Grains are settable through ``salt-ssh``. By
    default, these grains will *not* be persisted across reboots.

    See the "thin_dir" setting in :doc:`Roster documentation </topics/ssh/roster>`
    for more details.

Configuring Salt SSH
====================

Salt SSH takes its configuration from a master configuration file. Normally, this
file is in ``/etc/salt/master``. If one wishes to use a customized configuration file,
the ``-c`` option to Salt SSH facilitates passing in a directory to look inside for a
configuration file named ``master``.

Minion Config
---------------

.. versionadded:: 2015.5.1

Minion config options can be defined globally using the master configuration
option ``ssh_minion_opts``. It can also be defined on a per-minion basis with
the ``minion_opts`` entry in the roster.

Running Salt SSH as non-root user
=================================

By default, Salt read all the configuration from /etc/salt/. If you are running
Salt SSH with a regular user you have to modify some paths or you will get
"Permission denied" messages. You have to modify two parameters: ``pki_dir``
and ``cachedir``. Those should point to a full path writable for the user.

It's recommed not to modify /etc/salt for this purpose. Create a private copy
of /etc/salt for the user and run the command with ``-c /new/config/path``.

Define CLI Options with Saltfile
================================

If you are commonly passing in CLI options to ``salt-ssh``, you can create
a ``Saltfile`` to automatically use these options. This is common if you're
managing several different salt projects on the same server.

So you can ``cd`` into a directory that has a ``Saltfile`` with the following
YAML contents:

.. code-block:: yaml

    salt-ssh:
      config_dir: path/to/config/dir
      ssh_max_procs: 30
      ssh_wipe: True

Instead of having to call
``salt-ssh --config-dir=path/to/config/dir --max-procs=30 --wipe \* test.ping`` you
can call ``salt-ssh \* test.ping``.

Boolean-style options should be specified in their YAML representation.

.. note::

   The option keys specified must match the destination attributes for the
   options specified in the parser
   :py:class:`salt.utils.parsers.SaltSSHOptionParser`.  For example, in the
   case of the ``--wipe`` command line option, its ``dest`` is configured to
   be ``ssh_wipe`` and thus this is what should be configured in the
   ``Saltfile``.  Using the names of flags for this option, being ``wipe:
   True`` or ``w: True``, will not work.

Debugging salt-ssh
==================

One common approach for debugging ``salt-ssh`` is to simply use the tarball that salt
ships to the remote machine and call ``salt-call`` directly.

To determine the location of ``salt-call``, simply run ``salt-ssh`` with the ``-ltrace``
flag and look for a line containing the string, ``SALT_ARGV``. This contains the ``salt-call``
command that ``salt-ssh`` attempted to execute.

It is recommended that one modify this command a bit by removing the ``-l quiet``,
``--metadata`` and ``--output json`` to get a better idea of what's going on on the target system.

.. toctree::

    roster
