When Node Executors are invoked

Rundeck executes Command items on Nodes. The command may be part of a Workflow as defined in a Job, and it may be executed multiple times on different nodes.

Several "kinds" of Command items can be specified in Workflows:

1. "exec" commands - simple system command strings.
2. "script" commands - either embedded script content, or server-local script. files can be sent to the specified node and then executed with a set of input arguments.
3. "jobref" commands - references to other Jobs by name that will be executed with a set of input arguments.
4. custom - Users can use or create their own workflow step plugins.

Rundeck uses the NodeExecutor and FileCopier services as part of the process of executing these command types.

The procedure for executing an "exec" command is:

1. load the NodeExecutor provider for the node and context.
2. call the NodeExecutor#executeCommand method.

The procedure for executing a "script" command is:

1. load the FileCopier provider for the node and context.
2. call the FileCopier#copy* method.
3. load the NodeExecutor provider for the node and context.
4. Possibly execute an intermediate command (such as "chmod +x" on the copied file).
5. execute the NodeExecutor#executeCommand method, passing the filepath of the copied file, and any arguments to the script command.

Built-in Node Execution plugins

Rundeck includes the following node execution plugins.

local

local execution of a command.

jsch-ssh

remote execution of a command via SSH, requiring the "hostname", and "username" attributes on a node.

For FileCopier, these plugins:

local

creates a local temp file for a script.

jsch-scp

remote copy of a command via SCP, requiring the "hostname" and "username" attributes on a node.