ArribaSim fork offers a quick full grid

A new branch of OpenSim, ArribaSim, promises better performance than mainline OpenSim while maintaining full compatibility. And now there’s a packaged version of it, called Arriba Mini-Grid, that sets itself up with a single click.

The package is provided by Dorena’s World, a mid-sized German-language commercial grid.

In face, Dorena’s World has recently switched over to the new distribution, grid owner Dorena Verne told Hypergrid Business.

“Dorena’s World is the first grid running entirely under ArribaSim,” she said.

She said she was attracted to the distribution because the developer is extremely fast at responding to problem reports, and because the new distribution runs quickly.

That's me, relaxing on the first full grid I've ever set up.

That’s me, relaxing on the first full grid I’ve ever set up.

“It is a lot faster, without putting more demands on the hardware,” she said. “In fact, it uses less memory and CPU resources than the traditional, vanilla OpenSim.”

Read more about it at GridTalk.

The project claims to be fully compatible with mainline OpenSim, so that ArribaSim regions, for example, can be attached to standard OpenSim grids. Versions are available for connection to OSgrid and Metropolis.

ArribaSim is created and maintained by a German developer known only as “Freaky Tech.”

“I haven’t heard of this,” said OpenSim core developer Justin Clark-Casey. “As a general point, I do want to exercise a note of caution and say that people should make sure they trust a distribution before using it.”

Not actually a minigrid

The Arriba Mini-Grid is as easy, if not even easier, to use than the popular minigrid versions of OpenSim — Diva Distro, Sim-on-a-Stick or New World Studio.

However, it is a full grid, not a minigrid.

A minigrid, also known as a standalone, is a compact version of OpenSim that runs in a single server, so is limited in size to what that one server can handle. A full grid, however, uses one server for the central grid services such as maps and user inventories, and one or more additional servers to run the regions. As a result, it can grow as big as it needs to, simply by adding more region servers.

How does it work?

First, you download Arriba Mini-Grid — be patient, it’s 145 megabytes. Then unzip it. Then open up the folder you unzipped it to. You will see two files — a text file with your passwords, and a batch file called arriba-start.bat. Double-click on that second one, and give Windows permission to do stuff a few times.

Then you configure the Robust databases… just kidding, no configuration. You’re done. Seriously.

You will have three applications open on your computer — the OpenSim.exe application which is your region server, the Robust.exe application which is your central grid services, and the MoWeS application which runs your Apache web front end and your MySQL database.

The only thing missing is your viewer, but you can open that yourself.

ArribaSim's default login screen.

ArribaSim’s default login screen.

To log in, you will have to create a new grid in the grid manager. You might be tempted to try to log into localhost, which is what you would use if you were logging into a local Diva, a Sim-on-a-Stick, or a New World Studio. That’s what I tried doing, until I figured out that the viewer, by default, points localhost to the 9000 port used by minigrids instead of to the 8002 port used by full grids. So you have to add a new grid to your grid manager, with a loginURI of

Then log in with the avatar name of Testi Tester and the password arriba.

The Arriba Mini-Grid package comes with a very nice starter region, and is hypergrid-enabled. However, I couldn’t teleport out, possibly because of my router configuration or lack thereof.

ArribaSim also comes with a web front end based on MyOpenGrid‘s MWI interface.

Once you have your Arriba grid running, you can see your website here, and your splash page here.'

Maria Korolov

Maria Korolov is editor and publisher of Hypergrid Business. She has been a journalist for more than twenty years and has worked for the Chicago Tribune, Reuters, and Computerworld and has reported from over a dozen countries, including Russia and China.