In OpenSimulator (OpenSim), a
Standalone configuration and a Grid Server (using the ROBUST architecture) represent the two primary ways to deploy a virtual world.
1. Standalone Mode (Grid-in-a-Box)
In Standalone mode, all necessary services (User, Grid, Asset, and Inventory) run within a single process: OpenSim.exe.
Best For: Personal use, small private islands, artists, and testing.
Key Files: Configuration is primarily managed through OpenSim.ini and config-include/StandaloneCommon.ini.
Database: Typically uses SQLite for ease of setup, though it can use MySQL.
Network: Defaults to port 9000 for logins and region access.
Limitations: Difficult to scale; all regions must run on the same physical machine as the services.
2. Grid Mode (ROBUST Server)
In Grid mode, the services are separated from the region simulator. The services run in a standalone shell called Robust.exe, while regions run in one or more separate OpenSim.exe processes.
Best For: Large-scale virtual worlds with multiple regions hosted on different servers.
Key Files: Services are configured in Robust.ini, and simulators connect using config-include/GridCommon.ini.
Database: Requires MySQL; SQLite is not supported for full grid services.
Network: Uses port 8002 for public services (login) and port 8003 for private backend services (asset/inventory).
Scalability: Allows you to connect multiple "Simulators" (Region Servers) from different IP addresses to a single central "Grid Server".