8. Using a Single-Instance Galaxy on Any Alpha System With OpenVMS Alpha Version 7.2, you can run a single- instance Galaxy on any Alpha platform. This capability allows early adopters to evaluate OpenVMS Galaxy features, and most importantly, to develop and test Galaxy-aware applications without incurring the expense of setting up a full-scale Galaxy computing environment on a system capa- ble of running multiple instances of OpenVMS (for example, an AlphaServer 8400). A single-instance Galaxy running on any Alpha system is not an emulator. It is OpenVMS Galaxy code with Galaxy inter- faces and underlying operating system functions. All Galaxy APIs are present in a single-instance Galaxy (for example, resource management, shared memory access, event notifi- cation, locking for synchronization, and shared memory for global sections). Any application run on a single-instance Galaxy will exercise the exact same operating system code on a multiple instance Galaxy system. This is accomplished by creating the config- uration file SYS$SYSTEM:GLX$GCT.BIN, which OpenVMS reads into memory. On a Galaxy platform (for example, AlphaServer 8400), the console places configuration data in memory for OpenVMS to use. Once the configuration data is in memory, regardless of its origin, OpenVMS boots as a Galaxy instance. To use the Galaxy Configuration Utility to create a single- instance Galaxy on any Alpha System: Run the GCU on the OpenVMS Alpha system on which you want to use the single-instance Galaxy. If the GCU is run on a non-Galaxy system, it will prompt as to whether you want to create a single-instance Galaxy. Click on OK. The GCU next prompts for the amount of memory to desig- nate as shared memory. Enter any value that is a multiple of 8 megabytes. Note that you must specify at least 8 megabytes of shared memory if you want to boot as a Galaxy instance. This means the minimum Galaxy memory requirement is 72 megabytes. When the GCU has displayed the configuration, it will have already written the file GLX$GCT.BIN to the current di- rectory. You may exit the GCU at this point. If you made a mistake or want to alter the configuration, you can close the current model and repeat the process. To reboot the system as a Galaxy instance: 1. Copy the GLX$GCT.BIN file to SYS$SYSROOT:[SYSEXE]GLX$GCT.BIN 2. Shutdown the system. 3. Reboot with a conversational boot command (i.e. >>> B - FL 0,1 device) 4. SYSBOOT> SET GALAXY 1 5. SYSBOOT> CONTINUE Console output message is to be supplied.