Salt Super-Proxy

Salt plugin to automate the management and configuration of network devices at scale, without running (Proxy) Minions.

Using salt-sproxy, you can continue to benefit from the scalability, flexibility and extensibility of Salt, while you don’t have to manage thousands of (Proxy) Minion services. However, you are able to use both salt-sproxy and your (Proxy) Minions at the same time.

Why salt-sproxy

salt-sproxy can be used as a standalone tool to manage your devices without having any further requirements, as well as an extension to your existing Salt environment (if you already have). In other words, if you have a Salt installation where you manage some network devices and servers, installing salt-sproxy on your Master will allow you to run any Salt command as always, e.g., executing salt \* test.ping and salt-sproxy \* test.ping will have the exact same effect, and result. On top of that, using salt-sproxy allows you to manage other devices for which you don’t run (Proxy) Minions for.

Of course, if you don’t already have Salt, no problem, you can start managing your devices straight away, check out the quick start steps.

In brief, here are some benefits you can get by using salt-sproxy:

  • Say goodbye to the burden of managing hundreds of system services for the Proxy Minion processes.
  • Reuse your existing extension modules, templates, Pillars, States, etc., you may have already developed in your environment, transparently.
  • You can run it locally, on your own computer.
  • Python programming made a breeze - might go well with the ISalt package.
  • Integrates easily with your existing Salt environment (if you have), by installing the package on your Salt Master.
  • Can continue to leverage the event-driven automation and orchestration methodologies.
  • Can continue using any of the usual targeting mechanisms.
  • REST API, see also the Salt REST API documentation.
  • By sending events to a Salt Master, you are able to implement whatever auditing you need (e.g., what command was executed by who and when, etc.).
  • Benefit from inheriting _all_ the native Salt features and integrations contributed by thousands of users, and tested in hundreds of different environments, over almost a decade of development.

Is salt-sproxy a wrapper around salt-ssh?

No, nothing to do with salt-ssh. The core of salt-sproxy is a Runner loaded dynamically on runtime, that spins up a pool of child processes, each running a temporary light version of the Proxy Minion underneath; as soon as the execution is complete for a device, its associated Proxy Minion is shut down, and another one takes its place into the child processes bucket.

A source of confusion may also be the usage of the Roster interface, which, historically has only been used by salt-ssh, although the Roster is not tightly coupled with salt-ssh: it just happened to be the only use case so far. Essentially, the Roster simply provides a list of devices together with their credentials (e.g., similar to the inventory as dubbed in other automation frameworks) - and now has another use case in salt-sproxy.

Install

Install this package where you would like to manage your devices from. In case you need a specific Salt version, make sure you install it beforehand, otherwise this package will bring the latest Salt version available instead.

The package is distributed via PyPI, under the name salt-sproxy.

Execute:

pip install salt-sproxy

See Installation for more detailed installation notes.

Quick Start

See this recording for a live quick start:

In the above, minion1 is a dummy Proxy Minion, that can be used for getting started and make the first steps without connecting to an actual device, but get used to the salt-sproxy methodology.

The Master configuration file is /home/mircea/master, which is why the command is executed using the -c option specifying the path to the directory with the configuration file. In this Master configuration file, the pillar_roots option points to /srv/salt/pillar which is where salt-sproxy is going to load the Pillar data from. Accordingly, the Pillar Top file is under that path, /srv/salt/pillar/top.sls:

base:
  minion1:
    - dummy

This Pillar Top file says that the Minion minion1 will have the Pillar data from the dummy.sls from the same directory, thus /srv/salt/pillar/dummy.sls:

proxy:
  proxytype: dummy

In this case, it was sufficient to only set the proxytype field to dummy.

salt-sproxy can be used in conjunction with any of the available Salt Proxy modules, or others that you might have in your own environment. See https://docs.saltstack.com/en/latest/topics/proxyminion/index.html to understand how to write a new Proxy module if you require.

For example, let’s take a look at how we can manage a network device through the NAPALM Proxy:

In the above, in the same Python virtual environment as previously make sure you have NAPALM installed, by executing pip install napalm (see https://napalm.readthedocs.io/en/latest/installation/index.html for further installation requirements, depending on the platform you’re running on). The connection credentials for the juniper-router are stored in the /srv/salt/pillar/junos.sls Pillar, and we can go ahead and start executing arbitrary Salt commands, e.g., net.arp to retrieve the ARP table, or net.load_config to apply a configuration change on the router.

The Pillar Top file in this example was (under the same path as previously, as the Master config was the same):

base:
  juniper-router:
    - junos

Thanks to Tesuto for providing the virtual machine for the demos!

Usage

First off, make sure you have the Salt Pillar Top file correctly defined and the proxy key is available into the Pillar. For more in-depth explanation and examples, check this tutorial from the official SaltStack docs.

Once you have that, you can start using salt-sproxy even without any Proxy Minions or Salt Master running. To check, can start by executing:

$ salt-sproxy -L a,b,c --preview-target
- a
- b
- c

The syntax is very similar to the widely used CLI command salt, however the way it works is completely different under the hood:

salt-sproxy <target> <function> [<arguments>]

Usage Example:

$ salt-sproxy cr1.thn.lon test.ping
cr1.thn.lon:
    True

One of the most important differences between salt and salt-sproxy is that the former is aware of the devices available, thanks to the fact that the Minions connect to the Master, therefore salt has the list of targets already available. salt-sproxy does not have this, as it doesn’t require the Proxy Minions to be up and connected to the Master. For this reason, you will need to provide it a list of devices, or a Roster file that provides the list of available devices.

The following targeting options are available:

  • -E, --pcre: Instead of using shell globs to evaluate the target servers, use pcre regular expressions.
  • -L, --list: Instead of using shell globs to evaluate the target servers, take a comma or space delimited list of servers.
  • -G, --grain: Instead of using shell globs to evaluate the target use a grain value to identify targets, the syntax for the target is the grain key followed by a globexpression: "os:Arch*".
  • -P, --grain-pcre: Instead of using shell globs to evaluate the target use a grain value to identify targets, the syntax for the target is the grain key followed by a pcre regular expression: “os:Arch.*”.
  • -N, --nodegroup: Instead of using shell globs to evaluate the target use one of the predefined nodegroups to identify a list of targets.
  • -R, --range: Instead of using shell globs to evaluate the target use a range expression to identify targets. Range expressions look like %cluster.

Warning

Some of the targeting options above may not be available for some Roster modules.

To use a specific Roster, configure the proxy_roster (or simply roster) option into your Master config file, e.g.,

proxy_roster: ansible

Note

It is recommended to prefer the proxy_roster option in the favour of roster as the latter is used by Salt SSH. In case you want to use both salt-sproxy and Salt SSH, you may want to use different Roster files, which is why there are two different options.

salt-sproxy will evauluate both proxy_roster and roster, in this order.

With the configuration above, salt-sproxy would try to use the ansbile Roster module to compile the Roster file (typically /etc/salt/roster) which is structured as a regular Ansible Inventory file. This inventory should only provide the list of devices.

The Roster can also be specified on the fly, using the -R or --roster options, e.g., salt-sproxy cr1.thn.lon test.ping --roster=flat. In this example, we’d be using the flat Roster module to determine the list of devices matched by a specific target.

When you don’t specify the Roster into the Master config, or from the CLI, you can use salt-sproxy to target on or more devices using the glob or list target types, e.g., salt-sproxy cr1.thn.lon test.ping (glob) or salt-sproxy -L cr1.thn.lon,cr2.thn.lon test.ping (to target a list of devices, cr1.thn.lon and cr2.thn.lon, respectively).

Note that in any case (with or without the Roster), you will need to provide a valid list of Minions.

Docker

There are Docker images available should you need or prefer: https://github.com/mirceaulinic/salt-sproxy/pkgs/container/salt-sproxy.

You can see here the available tags: https://github.com/mirceaulinic/salt-sproxy/pkgs/container/salt-sproxy. Beware that the develop tag can be unstable so it’s recommended to rather use one of the specific tags corresponding to one of the latest versions.

These can be used in various scenarios. For example, if you would like to use salt-proxy but without installing it, and prefer to use Docker instead, you can define the following convoluted alias:

alias salt-sproxy='f(){ docker run --rm --network host -v $SALT_PROXY_PILLAR_DIR:/etc/salt/pillar/ -ti ghcr.io/mirceaulinic/salt-sproxy:develop salt-sproxy $@; }; f'

And in the SALT_PROXY_PILLAR_DIR environment variable, you set the path to the directory where you have the Pillars, e.g.,

export SALT_PROXY_PILLAR_DIR=/path/to/pillars/dir

With this setup, you would be able to go ahead and execute “as normally” (with the difference that the code is executed inside the container, however from the CLI it won’t look different):

salt-sproxy minion1 test.ping

More usage examples

See the following examples to help getting started with salt-sproxy:

Extension Modules

salt-sproxy is delivered together with a few extension modules that are dynamically loaded and immediately available. Please see below the documentation for these modules: