26.2.42. Salt 0.9.8 Release Notes

release:2012-03-21

Salt 0.9.8 is a big step forward, with many additions and enhancements, as well as a number of precursors to advanced future developments.

This version of Salt adds much more power to the command line, making the old hard timeout issues a thing of the past and adds keyword argument support. These additions are also available in the salt client API, making the available API tools much more powerful.

The new pillar system allows for data to be stored on the master and assigned to minions in a granular way similar to the state system. It also allows flexibility for users who want to keep data out of their state tree similar to 'external lookup' functionality in other tools.

A new way to extend requisites was added, the "requisite in" statement. This makes adding requires or watch statements to external state decs much easier.

Additions to requisites making them much more powerful have been added as well as improved error checking for sls files in the state system. A new provider system has been added to allow for redirecting what modules run in the background for individual states.

Support for OpenSUSE has been added and support for Solaris has begun serious development. Windows support has been significantly enhanced as well.

The matcher and target systems have received a great deal of attention. The default behavior of grain matching has changed slightly to reflect the rest of salt and the compound matcher system has been refined.

A number of impressive features with keyword arguments have been added to both the CLI and to the state system. This makes states much more powerful and flexible while maintaining the simple configuration everyone loves.

The new batch size capability allows for executions to be rolled through a group of targeted minions a percentage or specific number at a time. This was added to prevent the "thundering herd" problem when targeting large numbers of minions for things like service restarts or file downloads.

26.2.42.1. Upgrade Considerations

26.2.42.1.1. Upgrade Issues

There was a previously missed oversight which could cause a newer minion to crash an older master. That oversight has been resolved so the version incompatibility issue will no longer occur. When upgrading to 0.9.8 make sure to upgrade the master first, followed by the minions.

26.2.42.1.2. Debian/Ubuntu Packages

The original Debian/Ubuntu packages were called salt and included all salt applications. New packages in the ppa are split by function. If an old salt package is installed then it should be manually removed and the new split packages need to be freshly installed.

On the master:

# apt-get purge salt
# apt-get install salt-{master,minion}

On the minions:

# apt-get purge salt
# apt-get install salt-minion

And on any Syndics:

# apt-get install salt-syndic

The official Salt PPA for Ubuntu is located at: https://launchpad.net/~saltstack/+archive/salt

26.2.42.2. Major Features

26.2.42.2.1. Pillar

Pillar offers an interface to declare variable data on the master that is then assigned to the minions. The pillar data is made available to all modules, states, sls files etc. It is compiled on the master and is declared using the existing renderer system. This means that learning pillar should be fairly trivial to those already familiar with salt states.

26.2.42.2.2. CLI Additions

The salt command has received a serious overhaul and is more powerful than ever. Data is returned to the terminal as it is received, and the salt command will now wait for all running minions to return data before stopping. This makes adding very large --timeout arguments completely unnecessary and gets rid of long running operations returning empty {} when the timeout is exceeded.

When calling salt via sudo, the user originally running salt is saved to the log for auditing purposes. This makes it easy to see who ran what by just looking through the minion logs.

The salt-key command gained the -D and --delete-all arguments for removing all keys. Be careful with this one!

26.2.42.2.3. Running States Without a Master

The addition of running states without a salt-master has been added to 0.9.8. This feature allows for the unmodified salt state tree to be read locally from a minion. The result is that the UNMODIFIED state tree has just become portable, allowing minions to have a local copy of states or to manage states without a master entirely.

This is accomplished via the new file client interface in Salt that allows for the salt:// URI to be redirected to custom interfaces. This means that there are now two interfaces for the salt file server, calling the master or looking in a local, minion defined file_roots.

This new feature can be used by modifying the minion config to point to a local file_roots and setting the file_client option to local.

26.2.42.2.4. Keyword Arguments and States

State modules now accept the **kwargs argument. This results in all data in a sls file assigned to a state being made available to the state function.

This passes data in a transparent way back to the modules executing the logic. In particular, this allows adding arguments to the pkg.install module that enable more advanced and granular controls with respect to what the state is capable of.

An example of this along with the new debconf module for installing ldap client packages on Debian:

ldap-client-packages:
  pkg:
    - debconf: salt://debconf/ldap-client.ans
    - installed
    - names:
      - nslcd
      - libpam-ldapd
      - libnss-ldapd

26.2.42.2.5. Keyword Arguments and the CLI

In the past it was required that all arguments be passed in the proper order to the salt and salt-call commands. As of 0.9.8, keyword arguments can be passed in the form of kwarg=argument.

# salt -G 'type:dev' git.clone \
    repository=https://github.com/saltstack/salt.git cwd=/tmp/salt user=jeff

26.2.42.2.6. Matcher Refinements and Changes

A number of fixes and changes have been applied to the Matcher system. The most noteworthy is the change in the grain matcher. The grain matcher used to use a regular expression to match the passed data to a grain, but now defaults to a shell glob like the majority of match interfaces in Salt. A new option is available that still uses the old style regex matching to grain data called grain-pcre. To use regex matching in compound matches use the letter P.

For example, this would match any ArchLinux or Fedora minions:

# salt --grain-pcre 'os:(Arch:Fed).*' test.ping

And the associated compound matcher suitable for top.sls is P:

P@os:(Arch|Fed).*

NOTE: Changing the grains matcher from pcre to glob is backwards incompatible.

Support has been added for matching minions with Yahoo's range library. This is handled by passing range syntax with -R or --range arguments to salt.

More information at: https://github.com/grierj/range/wiki/Introduction-to-Range-with-YAML-files

26.2.42.2.7. Requisite "in"

A new means to updating requisite statements has been added to make adding watchers and requires to external states easier. Before 0.9.8 the only way to extend the states that were watched by a state outside of the sls was to use an extend statement:

include:
  - http
extend:
  apache:
    service:
      - watch:
        - pkg: tomcat

tomcat:
  pkg:
    - installed

But the new Requisite in statement allows for easier extends for requisites:

include:
  - http

tomcat:
  pkg:
    - installed
    - watch_in:
      - service: apache

Requisite in is part of the extend system, so still remember to always include the sls that is being extended!

26.2.42.2.8. Providers

Salt predetermines what modules should be mapped to what uses based on the properties of a system. These determinations are generally made for modules that provide things like package and service management. The apt module maps to pkg on Debian and the yum module maps to pkg on Fedora for instance.

Sometimes in states, it may be necessary for a non-default module to be used for the desired functionality. For instance, an Arch Linux system may have been set up with systemd support. Instead of using the default service module detected for Arch Linux, the systemd module can be used:

http:
  service:
    - running
    - enable: True
    - provider: systemd

Default providers can also be defined in the minion config file:

providers:
  service: systemd

When default providers are passed in the minion config, then those providers will be applied to all functionality in Salt, this means that the functions called by the minion will use these modules, as well as states.

26.2.42.2.9. Requisite Glob Matching

Requisites can now be defined with glob expansion. This means that if there are many requisites, they can be defined on a single line.

To watch all files in a directory:

http:
  service:
    - running
    - enable: True
    - watch:
      - file: /etc/http/conf.d/*

This example will watch all defined files that match the glob /etc/http/conf.d/*

26.2.42.2.10. Batch Size

The new batch size option allows commands to be executed while maintaining that only so many hosts are executing the command at one time. This option can take a percentage or a finite number:

salt '*' -b 10 test.ping

salt -G 'os:RedHat' --batch-size 25% apache.signal restart

This will only run test.ping on 10 of the targeted minions at a time and then restart apache on 25% of the minions matching os:RedHat at a time and work through them all until the task is complete. This makes jobs like rolling web server restarts behind a load balancer or doing maintenance on BSD firewalls using carp much easier with salt.

26.2.42.2.11. Module Updates

This is a list of notable, but non-exhaustive updates with new and existing modules.

Windows support has seen a flurry of support this release cycle. We've gained all new file, network, and shadow modules. Please note that these are still a work in progress.

For our ruby users, new rvm and gem modules have been added along with the associated states

The virt module gained basic Xen support.

The yum module gained Scientific Linux support.

The pkg module on Debian, Ubuntu, and derivatives force apt to run in a non-interactive mode. This prevents issues when package installation waits for confirmation.

A pkg module for OpenSUSE's zypper was added.

The service module on Ubuntu natively supports upstart.

A new debconf module was contributed by our community for more advanced control over deb package deployments on Debian based distributions.

The mysql.user state and mysql module gained a password_hash argument.

The cmd module and state gained a shell keyword argument for specifying a shell other than /bin/sh on Linux / Unix systems.

New git and mercurial modules have been added for fans of distributed version control.

26.2.42.3. In Progress Development

26.2.42.3.1. Master Side State Compiling

While we feel strongly that the advantages gained with minion side state compiling are very critical, it does prevent certain features that may be desired. 0.9.8 has support for initial master side state compiling, but many more components still need to be developed, it is hoped that these can be finished for 0.9.9.

The goal is that states can be compiled on both the master and the minion allowing for compilation to be split between master and minion. Why will this be great? It will allow storing sensitive data on the master and sending it to some minions without all minions having access to it. This will be good for handling ssl certificates on front-end web servers for instance.

26.2.42.3.2. Solaris Support

Salt 0.9.8 sees the introduction of basic Solaris support. The daemon runs well, but grains and more of the modules need updating and testing.

26.2.42.3.3. Windows Support

Salt states on windows are now much more viable thanks to contributions from our community! States for file, service, local user, and local group management are more fully fleshed out along with network and disk modules. Windows users can also now manage registry entries using the new "reg" module.