CLI Reference

Ensemble Launcher provides the el command-line interface for launching ensembles without writing Python scripts.

Commands

el --help
el start --help
el stop --help

el start

Launch an ensemble from a JSON configuration file.

el start ENSEMBLE_FILE [OPTIONS]

In normal mode, it blocks until all tasks finish and writes results.json. In cluster mode (when the launcher config has "cluster": true), it starts the orchestrator in the background and returns immediately.

Options

Option	Description
--system-config-file	Path to system configuration JSON
--launcher-config-file	Path to launcher configuration JSON
--nodes-str	Comma-separated compute nodes, e.g. "node-001,node-002"

Examples

Basic execution:

el start my_ensemble.json

With custom configurations:

el start my_ensemble.json \
    --system-config-file system.json \
    --launcher-config-file launcher.json

Specify compute nodes:

el start my_ensemble.json \
    --nodes-str "node-001,node-002,node-003,node-004"

Cluster mode:

el start my_ensemble.json --launcher-config-file cluster_launcher.json
# Returns immediately; orchestrator runs in background

# ... submit tasks from Python ...

el stop

el stop

Send SIGTERM to a cluster-mode orchestrator started with el start, triggering graceful shutdown.

el stop

The PID of the background process is stored in .el_launcher.pid in the working directory.