salt/doc/topics/ssh/roster.rst

Salt Rosters

Salt rosters are pluggable systems added in Salt 0.17.0 to facilitate the salt-ssh system. The roster system was created because salt-ssh needs a means to identify which systems need to be targeted for execution.

all-salt.roster

Note

The Roster System is not needed or used in standard Salt because the master does not need to be initially aware of target systems, since the Salt Minion checks itself into the master.

Since the roster system is pluggable, it can be easily augmented to attach to any existing systems to gather information about what servers are presently available and should be attached to by salt-ssh. By default the roster file is located at /etc/salt/roster.

How Rosters Work

The roster system compiles a data structure internally referred to as targets. The targets is a list of target systems and attributes about how to connect to said systems. The only requirement for a roster module in Salt is to return the targets data structure.

Targets Data

The information which can be stored in a roster target is the following:

<Salt ID>:       # The id to reference the target system with
    host:        # The IP address or DNS name of the remote host
    user:        # The user to log in as
    passwd:      # The password to log in with

    # Optional parameters
    port:        # The target system's ssh port number
    sudo:        # Boolean to run command via sudo
    sudo_user:   # Str: Set this to execute Salt as a sudo user other than root.
                 # This user must be in the same system group as the remote user
                 # that is used to login and is specified above. Alternatively,
                 # the user must be a super-user.
    tty:         # Boolean: Set this option to True if sudo is also set to
                 # True and requiretty is also set on the target system
    priv:        # File path to ssh private key, defaults to salt-ssh.rsa
                 # The priv can also be set to agent-forwarding to not specify
                 # a key, but use ssh agent forwarding
    timeout:     # Number of seconds to wait for response when establishing
                 # an SSH connection
    minion_opts: # Dictionary of minion opts
    thin_dir:    # The target system's storage directory for Salt
                 # components. Defaults to /tmp/salt-<hash>.
    cmd_umask:   # umask to enforce for the salt-call command. Should be in
                 # octal (so for 0o077 in YAML you would do 0077, or 63)

Target Defaults

The roster_defaults dictionary in the master config is used to set the default login variables for minions in the roster so that the same arguments do not need to be passed with commandline arguments.

roster_defaults:
  user: daniel
  sudo: True
  priv: /root/.ssh/id_rsa
  tty: True

thin_dir

Salt needs to upload a standalone environment to the target system, and this defaults to /tmp/salt-<hash>. This directory will be cleaned up per normal systems operation.

If you need a persistent Salt environment, for instance to set persistent grains, this value will need to be changed.