The ASCI Red supercomputer was a distributed memory MIMD (Multiple Instruction, Multiple Data) message-passing computer. The design provided high degrees of scalability for I/O, memory, compute nodes, storage capacity, and communications; standard parallel interfaces also made it possible to port parallel applications to the machine. The machine was structured into four partitions: Compute, Service, I/O, and System. Parallel applications executed in the Compute Partition which contained nodes optimized for floating point performance. The compute nodes had only the features required for efficient computation – they were not purposed for general interactive services. The Service Partition provided an integrated, scalable host that supported interactive users (log-in sessions), application development, and system administration. The I/O Partition supported disk I/O, a scalable parallel file system and network services. The System Partition supported initial booting and system Reliability, Availability, and Serviceability (RAS) capabilities.