# SaltStack Master v3000.1

Dockerfile to build a [SaltStack](https://www.saltstack.com) Master image for the Docker opensource container platform.

SaltStack Master is set up in the Docker image using the install from git source method as documented in the the [official bootstrap](https://docs.saltstack.com/en/latest/topics/tutorials/salt_bootstrap.html) documentation.

For other methods to install SaltStack please refer to the [Official SaltStack Installation Guide](https://docs.saltstack.com/en/latest/topics/installation/index.html).

## Table of Contents

- [Installation](#installation)
  - [Changelog](CHANGELOG.md)
- [Quick Start](#quick-start)
- [Configuration](#configuration)
  - [Custom Recipes](#custom-recipes)
  - [Minion Keys](#minion-keys)
  - [Master Signed Keys](#master-signed-keys)
  - [Host Mapping](#host-mapping)
  - [Git Fileserver](#git-fileserver)
    - [GitPython](#gitpython)
    - [PyGit2](#pygit2)
  - [Logs](#logs)
  - [Available Configuration Parameters](#available-configuration-parameters)
- [Usage](#usage)
- [Shell Access](#shell-access)
- [References](#references)

## Installation

Automated builds of the image are available on [Dockerhub](https://hub.docker.com/r/cdalvaro/saltstack-master/) and is the recommended method of installation.

```sh
docker pull cdalvaro/saltstack-master:3000.1
```

You can also pull the latest tag which is built from the repository `HEAD`

```sh
docker pull cdalvaro/saltstack-master:latest
```

or from [Quay.io](https://quay.io/repository/cdalvaro/saltstack-master) too.

```sh
docker pull quay.io/cdalvaro/saltstack-master:latest
```

Alternatively you can build the image locally.

```sh
docker build -t cdalvaro/saltstack-master github.com/cdalvaro/saltstack-master
```

## Quick Start

The quickest way to get started is using [docker-compose](https://docs.docker.com/compose/).

```sh
wget https://raw.githubusercontent.com/cdalvaro/saltstack-master/master/docker-compose.yml
```

Start SaltStack master using:

```sh
docker-compose up --detach
```

Alternatively, you can manually launch the `saltstack-master`  container:

```sh
docker run --name salt_master --detach \
    --publish 4505:4505/tcp --publish 4506:4506/tcp \
    --env 'SALT_LOG_LEVEL=info' \
    --volume $(pwd)/roots/:/home/salt/data/srv/ \
    --volume $(pwd)/keys/:/home/salt/data/keys/ \
    cdalvaro/saltstack-master:3000.1
```

## Configuration

### Custom Recipes

In order to provide salt with your custom recipes you must mount the volume `/home/salt/data/srv/` with your `roots` directory.

### Minion Keys

Minion keys can be added automatically on startup to SaltStack master by mounting the volume `/home/salt/data/keys` and copying the minion keys inside `keys/minions/` directory.

It is also important to know that, in order to keep your keys after removing the container, the keys directory must be mounted.

```sh
mkdir -p keys/minions
rsync root@minion1:/etc/salt/pki/minion/minion.pub keys/minions/minion1

docker run --name salt_master -d \
    --publish 4505:4505/tcp --publish 4506:4506/tcp \
    --env 'SALT_LOG_LEVEL=info' \
    --volume $(pwd)/roots/:/home/salt/data/srv/ \
    --volume $(pwd)/keys/:/home/salt/data/keys/ \
    cdalvaro/saltstack-master:3000.1
```

### Master Signed Keys

It is possible to use signed master keys by establishing the environment variable `SALT_MASTER_SIGN_PUBKEY` to `True`.

```sh
docker run --name salt_stack --detach \
    --publish 4505:4505/tcp --publish 4506:4506/tcp \
    --env 'SALT_LOG_LEVEL=info' \
    --env 'SALT_MASTER_SIGN_PUBKEY=True'
    --volume $(pwd)/roots/:/home/salt/data/srv/ \
    --volume $(pwd)/keys/:/home/salt/data/keys/ \
    cdalvaro/saltstack-master:3000.1
```

The container will create the `master_sign` key and its signature. More information about how to configure the minion service can be found [here](https://docs.saltstack.com/en/latest/topics/tutorials/multimaster_pki.html#prepping-the-minion-to-verify-received-public-keys).

Additionally, you can generate new keys by executing the following command:

```sh
docker run --name salt_stack -it --rm \
    --volume $(pwd)/keys/:/home/salt/data/keys/ \
    cdalvaro/saltstack-master:3000 app:gen-signed-keys other_master_sign
```

The newly created keys will appear inside `keys/generated/other_master_sign` directory.

### Host Mapping

Per default the container is configured to run `salt-master` as user and group `salt` with `uid` and `gid` `1000`. From the host it appears as if the mounted data volumes are owned by the host's user/group `1000` and maybe leading to unfavorable effects.

Also the container processes seem to be executed as the host's user/group `1000`. The container can be configured to map the uid and gid of git to different ids on host by passing the environment variables `USERMAP_UID` and `USERMAP_GID`. The following command maps the ids to the current user and group on the host.

```sh
docker run --name salt_stack -it --rm \
    --env "USERMAP_UID=$(id -u)" --env "USERMAP_GID=$(id -g)" \
    --volume $(pwd)/roots/:/home/salt/data/srv/ \
    --volume $(pwd)/keys/:/home/salt/data/keys/ \
    cdalvaro/saltstack-master:3000.1
```

### Git Fileserver

This image uses [GitPython](https://github.com/gitpython-developers/GitPython) and [PyGit2](https://www.pygit2.org) as gitfs backends to allow Salt to serve files from git repositories.

It can be enabled by adding `gitfs` to the [`fileserver_backend`](https://docs.saltstack.com/en/latest/ref/configuration/master.html#std:conf_master-fileserver_backend) list (see [Available Configuration Parameters](#available-configuration-parameters)), and configuring one or more repositories in [`gitfs_remotes`](https://docs.saltstack.com/en/latest/ref/configuration/master.html#std:conf_master-gitfs_remotes).

#### GitPython

The default name for the ssh key is `gitfs_ssh` but it can be changed with the env variables `SALT_GITFS_SSH_PRIVATE_KEY` and `SALT_GITFS_SSH_PUBLIC_KEY`.

This keys must be placed inside `/home/salt/data/keys` directory.

#### PyGit2

You can create an ssh key for pygit2 with the following command:

```sh
ssh-keygen -f gitfs_pygit2 -C 'gitfs@example.com'
```

Place it wherever you want inside the container and specify its path with the configuration parameters: `gitfs_pubkey`  and `gitfs_privkey`  in your `.conf` file.

For example:

```yml
gitfs_provider: pygit2
gitfs_privkey: /home/salt/data/keys/gitfs/gitfs_ssh
gitfs_pubkey: /home/salt/data/keys/gitfs/gitfs_ssh.pub
```

**Important Note**

If you get the following error while using `gitfs` with `pygit2`

```plain
_pygit2.GitError: Failed to authenticate SSH session: Unable to send userauth-publickey request
```

look if your private key hash empty lines at the bottom of the file and suppress them for solving the error.

### Logs

Salt logs are accessible by mounting the volume `/home/salt/data/logs/`.

Inside that directory you could find `supervisor/` logs and `salt/` logs:

```sh
docker run --name salt_master --detach \
    --publish 4505:4505/tcp --publish 4506:4506/tcp \
    --env 'SALT_LOG_LEVEL=info' \
    --volume $(pwd)/roots/:/home/salt/data/srv/ \
    --volume $(pwd)/keys/:/home/salt/data/keys/ \
    --volume $(pwd)/logs/:/home/salt/data/logs/ \
    cdalvaro/saltstack-master:3000.1
```

Check [Available Configuration Parameters](#available-configuration-parameters) section for configuring logrotate.

### Available Configuration Parameters

Please refer the docker run command options for the `--env-file` flag where you can specify all required environment variables in a single file. This will save you from writing a potentially long docker run command. Alternatively you can use docker-compose.

Below is the list of available options that can be used to customize your SaltStack master installation.

| Parameter | Description |
|:----------|:------------|
| `DEBUG` | Set this to `true` to enable entrypoint debugging. |
| `TIMEZONE` | Set the container timezone. Defaults to `UTC`. Values are expected to be in Canonical format. Example: `Europe/Madrid`. See the list of [acceptable values](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones). |
| `SALT_LOG_LEVEL` | The level of messages to send to the console. One of 'garbage', 'trace', 'debug', info', 'warning', 'error', 'critical'. Default: `warning` |
| `SALT_LOG_ROTATE_FREQUENCY` | Logrotate frequency for salt logs. Available options are 'daily', 'weekly', 'monthly', and 'yearly'. Default: `weekly` |
| `SALT_LOG_ROTATE_RETENTION` | Keep x files before deleting old log files. Defaults: `52` |
| `SALT_LEVEL_LOGFILE` | The level of messages to send to the log file. One of 'garbage', 'trace', 'debug', info', 'warning', 'error', 'critical'. Default: `warning` |
| `SALT_MASTER_SIGN_PUBKEY` | Sign the master auth-replies with a cryptographic signature of the master's public key. Possible values: 'True' or 'False'. Default: `False` |
| `SALT_MASTER_USE_PUBKEY_SIGNATURE` | Instead of computing the signature for each auth-reply, use a pre-calculated signature. This option requires `SALT_MASTER_SIGN_PUBKEY` set to 'True'. Possible values: 'True' or 'False'. Default: `True` |
| `SALT_MASTER_SIGN_KEY_NAME` | The customizable name of the signing-key-pair without suffix. Default: `master_sign` |
| `SALT_MASTER_PUBKEY_SIGNATURE` | The name of the file in the master's pki-directory that holds the pre-calculated signature of the master's public-key. Default: `master_pubkey_signature` |
| `SALT_MASTER_ROOT_USER` | Forces `salt-master` to be runned as `root` instead of `salt`. Default: `False` |
| `SALT_GITFS_SSH_PRIVATE_KEY` | The name of the ssh private key for gitfs. Default: `gitfs_ssh` |
| `SALT_GITFS_SSH_PUBLIC_KEY` | The name of the ssh public key for gitfs. Default: `gitfs_ssh.pub` |
| `USERMAP_UID` | Sets the uid for user `salt` to the specified uid. Default: `1000`. |
| `USERMAP_GID` | Sets the gid for user `salt` to the specified gid. Default: `1000`. |

Any parameter not listed in the above table and available in the following [link](https://docs.saltstack.com/en/latest/ref/configuration/examples.html#configuration-examples-master), can be set by creating the directory `config` and adding into it a `.conf` file with the desired parameters:

```sh
mkdir config
cat > config/ports.conf << EOF
# The tcp port used by the publisher:
publish_port: 3505
# The port used by the communication interface.
ret_port: 3506
EOF

docker run --name salt_master -d \
    --publish 3505:3505/tcp --publish 3506:3506/tcp \
    --env 'SALT_LOG_LEVEL=info' \
    --volume $(pwd)/roots/:/home/salt/data/srv/ \
    --volume $(pwd)/keys/:/home/salt/data/keys/ \
    --volume $(pwd)/config/:/home/salt/data/config/ \
    cdalvaro/saltstack-master:3000.1
```

## Usage

To test which salt minions are listening the following command can be executed directly from the host machine:

```sh
docker exec -it salt_master salt '*' test.ping
```

Then, you can apply salt states to your minions:

```sh
docker exec -it salt_master salt '*' state.apply [state]
```

## Shell Access

For debugging and maintenance purposes you may want access the container shell. If you are using docker version 1.3.0 or higher you can access a running container shell using docker exec command.

```sh
docker exec -it salt_master bash
```

## References

- https://docs.saltstack.com/en/latest/topics/installation/index.html
- https://docs.saltstack.com/en/latest/topics/tutorials/salt_bootstrap.html
- https://github.com/saltstack/salt/releases