Unix File System
Backend nodes are reserved for executing memory demanding and long running applications. They are the most powerful, but also most power consuming part of a cluster as they make up around 98% of it. Since these nodes are not directly accessable by the user, a scheduler manages their access. In order to run on these nodes, a batch job needs to be submitted to the batch system via a scheduler specific command.
Copy nodes are reserved for transfering data to or from a cluster. They usually offer a better connection than other nodes and minimize the disturbance of other users on the system. Depending on the facility, software installed on these nodes may differ from other ones due to their restricted use case, though not every facility chooses to install a designated copy node at all. As an alternative login node may be used to move data between systems.
Synonym for login node.
Login nodes are reserved for connecting to the cluster of a facility. Most of the time they can also be used for testing and performing interactive tasks (e.g. the analysis of previously collected application profiles). These test runs should generally not exceed execution times of just a few minutes and may only be used to verify that your software is running correctly on the system and its environment before submitting batch jobs to the batch system.
Random Access Memory (RAM)