Server configuration and dependencies

Silo is in active development before 1.0. These guides are updated frequently.

The default installation needs only a few environment values. Libraries, providers, accounts, and most day-to-day settings live in the admin web app.

Environment configuration

Set these in .env beside the Compose file:

Value	What it controls
MEDIA_ROOT	Media directory on the Docker host
MEDIA_CONTAINER_ROOT	Where that directory appears inside Silo
SILO_DATA_ROOT	Host directory for Silo’s data (see Docker reference)
SILO_IMAGE	Server image tag or digest
POSTGRES_PASSWORD	Password for the bundled database, used when it is first created
SECRET_KEY	Key that encrypts stored credentials
POSTGRES_TUNE	Automatic PostgreSQL tuning, auto by default

Changing POSTGRES_PASSWORD in an existing .env does not change the password PostgreSQL already stored. Changing SECRET_KEY makes existing encrypted credentials unreadable.

docker compose config prints the full configuration with passwords and keys filled in. Use docker compose config --quiet to check the files without printing them, and never paste the full output into a public report.

Admin-managed settings

Sign in as an admin and open Admin > Settings. Change one group at a time, save, and follow any restart notice. Some values apply live; others need a restart.

A value set in the environment can override the stored setting. For example, SILO_TRUSTED_PROXIES replaces the Trusted proxies setting on every start. Manage each value in one place.

External PostgreSQL and Redis

The default Compose file runs both services locally. It sets DATABASE_URL and REDIS_URL for the silo service directly and waits for both bundled services to be healthy, so adding different values to .env changes nothing.

To use existing servers, write a Compose file or override that:

• sets the external DATABASE_URL and REDIS_URL on the silo service
• removes the depends_on entries for the bundled services
• leaves out the bundled postgres and redis services
• keeps the media, plugin, artwork, compatibility, transcode, and catalog seed mounts
• uses the same SECRET_KEY for every Silo server and node

The database needs the pgvector extension; the default stack uses PostgreSQL 18. Check the merged files before starting:

docker compose -f docker-compose.yml -f your-override.yml config --quiet

PostgreSQL is required. Redis is optional for a single integrated or api server and required once you add proxy or transcode nodes.

Shared memory for your own PostgreSQL container

Size /dev/shm when you create your own PostgreSQL container. The bundled postgres service sets shm_size from POSTGRES_SHM_SIZE (8gb by default), but your container starts with Docker’s 64 MB default, which can be too small for PostgreSQL’s parallel queries. In Compose:

services:
  postgres:
    shm_size: 2gb

With docker run, or in a container manager’s extra-arguments field, pass --shm-size=2g. The value sets a tmpfs limit; it does not allocate that memory at startup. The bundled service uses 8gb if you want a starting point.

If the limit is too small, some catalog queries fail even though Silo keeps running and the disk has free space:

ERROR: could not resize shared memory segment "/PostgreSQL.1938557030" to 8388608 bytes: No space left on device (SQLSTATE 53100)

PostgreSQL installed directly on a host or VM does not use Docker’s shm_size setting. If shared-memory allocation fails there, check the free space in the host’s /dev/shm and increase its tmpfs size or free capacity.

PostgreSQL tuning

With POSTGRES_TUNE=auto, Silo tunes the database for its workload with ALTER SYSTEM at startup. Settings that need a database restart are logged by name on every start until PostgreSQL restarts. Restart both services together during a quiet period, because restarting PostgreSQL alone drops Silo’s connections:

docker compose restart postgres silo

Set POSTGRES_TUNE=off before starting Silo if you manage PostgreSQL settings yourself, and for an external database: automatic detection measures the Silo container, not the database host. Turning tuning off leaves settings already written to postgresql.auto.conf in place; reset them yourself if needed. The other POSTGRES_TUNE_* values in .env.example override the detected memory, CPU count, and storage type.

Plan PostgreSQL major-version upgrades separately from Silo updates.

Server modes

Mode	Purpose
integrated	Default single-host server
api	Main server for a custom distributed setup
proxy	Remote streaming node
transcode	Remote conversion worker

Separate nodes need the shared database, Redis, and encryption key. See Transcode nodes.

Logging

See Logs and monitoring.