Microsoft SQL Server Express
Overview
Microsoft SQL Server 2022 Express runs alongside PostgreSQL for Silver projects that require Microsoft SQL Server compatibility.
Status:
Operational
Verified version:
Microsoft SQL Server 2022 Express Edition (64-bit)
Linux
Version 16.0.4255.1
Service Information
| Property | Value |
|---|---|
| Container | mssql |
| Image | mcr.microsoft.com/mssql/server:2022-latest |
| Edition | Express |
| Docker network | internal |
| Compose location | /srv/docker/mssql/docker-compose.yml |
| Data location | /srv/docker/mssql/data |
Port 1433 is not published by Docker or exposed through Nginx Proxy Manager. Applications connect privately over the internal Docker network using hostname mssql.
Server-side administration must use docker exec or another container attached to internal; there is no host-bound SQL port in the current configuration.
Secrets
The SA password is stored outside the repository:
/srv/secrets/company.env
MSSQL_SA_PASSWORD
Never commit the value to Git or place it directly in the Compose file.
Deployment
Docker Compose must be given the secrets file for interpolation:
cd /srv/docker/mssql
docker compose --env-file /srv/secrets/company.env up -d
The Compose env_file: setting passes variables into the container. It does not make them available while Compose resolves ${MSSQL_SA_PASSWORD}, which is why --env-file is required.
Validate startup:
docker ps
docker logs mssql
Expected log message:
SQL Server is now ready for client connections.
Data Directory Permissions
The SQL Server container runs as UID and GID 10001. For a new, empty deployment, initialize the bind-mounted directory with:
sudo mkdir -p /srv/docker/mssql/data
sudo chown -R 10001:10001 /srv/docker/mssql/data
sudo chmod -R 700 /srv/docker/mssql/data
Do not delete or recreate the directory after databases exist. Removing /srv/docker/mssql/data destroys the persisted SQL Server data.
Troubleshooting
Variable Is Not Set
If Compose reports that MSSQL_SA_PASSWORD is unset and defaults to a blank string, use the required docker compose --env-file /srv/secrets/company.env up -d command.
System Directory Permission Denied
If [/.system] cannot be created, verify that /srv/docker/mssql/data is owned by 10001:10001 with mode 700.
Password Validation Failed
Confirm that the password meets SQL Server complexity requirements and that Compose resolved MSSQL_SA_PASSWORD from the secrets file.
Related Documentation
- docs/server.md
- docs/services.md
- docs/security.md
- docs/secrets.md
- docs/backups.md
- dbgate/README.md
- postgres/README.md