========================
Salt 0.9.0 Release Notes
========================

:release: 2011-08-27

Salt 0.9.0 is here. This is an exciting release, 0.9.0 includes the new network
topology features allowing peer salt commands and masters of masters via the
syndic interface.

0.9.0 also introduces many more modules, improvements to the API and
improvements to the ZeroMQ systems.

Download!
---------

The Salt source can be downloaded from the salt GitHub site:

:download:`salt-0.9.0.tar.gz`

Or from PyPI:

https://pypi.python.org/packages/source/s/salt/salt-0.9.0.tar.gz

Here is the md5sum:

9a925da04981e65a0f237f2e77ddab37

For instructions on how to set up Salt please see the :ref:`installation`
instructions.

New Features
------------

Salt Syndic
```````````

The new :ref:`Syndic interface <syndic>` allows a master to be
commanded via another higher level salt master. This is a powerful solution
allowing a master control structure to exist, allowing salt to scale to much
larger levels then before.

Peer Communication
``````````````````

0.9.0 introduces the capability for a minion to call a publication on the
master and receive the return from another set of minions. This allows salt
to act as a communication channel between minions and as a general
infrastructure message bus.

Peer communication is turned off by default but can be enabled via the ``peer``
option in the master configuration file. Documentation on the new :ref:`Peer
interface <peer>`.

Easily Extensible API
`````````````````````

The minion and master classes have been redesigned to allow for specialized
minion and master servers to be easily created. An example on how this is done
for the master can be found in the ``master.py`` salt module:

:blob:`salt/master.py`

The ``Master`` class extends the ``SMaster`` class and set up the main master
server.

The minion functions can now also be easily added to another application via
the ``SMinion`` class, this class can be found in the ``minion.py`` module:

:blob:`salt/minion.py`

Cleaner Key Management
``````````````````````

This release changes some of the key naming to allow for multiple master keys
to be held based on the type of minion gathering the master key.

The -d option has also been added to the salt-key command allowing for easy
removal of accepted public keys.

The --gen-keys option is now available as well for salt-key, this allows
for a salt specific RSA key pair to be easily generated from the command line.

Improved 0MQ Master Workers
```````````````````````````

The 0MQ worker system has been further refined to be faster and more robust.
This new system has been able to handle a much larger load than the previous
setup. The new system uses the IPC protocol in 0MQ instead of TCP.

New Modules
-----------

Quite a few new modules have been made.

New Minion Modules
``````````````````

apache
~~~~~~

Work directly with apache servers, great for managing balanced web servers

cron
~~~~

Read out the contents of a systems crontabs

mdadm
~~~~~

Module to manage raid devices in Linux, appears as the ``raid`` module

mysql
~~~~~

Gather simple data from MySQL databases

ps
~~

Extensive utilities for managing processes

publish
~~~~~~~

Used by the peer interface to allow minions to make publications