Salt rosters are pluggable systems added in Salt 0.17.0 to facilitate the
The roster system was created because
salt-ssh needs a means to
identify which systems need to be targeted for execution.
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.
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.
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 priv: # File path to ssh private key, defaults to salt-ssh.rsa timeout: # Number of seconds to wait for response when establishing # an SSH connection timeout: # Number of seconds to wait for response minion_opts: # Dictionary of minion opts thin_dir: # The target system's storage directory for Salt # components. Defaults to /tmp/salt-<hash>.
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.