synctl

Start Synapse server

$ synctl start

$ synctl stop

$ synctl restart

$ synctl start [/path/to/homeserver.yaml]

$ synctl start -w [/path/to/worker.yaml]

$ synctl restart -a [/path/to/workers/]

synctl {start|stop|restart} [configfile] [options]

synctl is the control interface for Matrix Synapse, the reference homeserver implementation for the Matrix communication protocol. It manages starting, stopping, and restarting the Synapse server and its worker processes.
For single-instance deployments, synctl operates on the main homeserver process. For scaled deployments using workers, the -a option manages all worker processes defined in a configuration directory.
Configuration files use YAML format and define server settings, database connections, federation parameters, and resource limits.

start

Start Synapse server or worker.

Stop Synapse server or worker.

Restart Synapse server or worker.

Path to configuration file (default: homeserver.yaml).

Operate on a single worker using specified config file.

Operate on all workers in directory and main process.

SYNAPSE_CACHE_FACTOR
: Controls memory cache size. Default is 0.5. Decrease to reduce RAM usage or increase for better performance.

The configuration file must exist and be valid YAML. When using workers, each worker needs its own configuration file. Memory usage can be significant; tune SYNAPSECACHEFACTOR accordingly. Requires Python 3 and dependencies installed.

Synapse is developed by Element (formerly New Vector) as the reference implementation of the Matrix protocol. Matrix is an open standard for decentralized, real-time communication. Synapse was first released in 2014 and remains the most widely deployed Matrix homeserver.

register_new_matrix_user(1), hash_password(1), systemctl(1)