Remote machines

EasyHybrid can run its simulations on other computers: a workstation reached by ssh, or a cluster with the SLURM scheduler. The jobs are submitted, monitored in the Process Manager and fetched back as if they had run locally.

Simulate > Run Simulations On chooses where the next simulations run: This Computer or one of the configured machines.

Simulate > Remote Machines... (Figure 1) configures the machines:

• Machine / Name / SSH host: the host is best an alias of ~/.ssh/config (user, key, port and jump host come from there). EasyHybrid uses ssh keys only and stores no password: ssh <host> in a terminal must log in without a password. Add SSH Host... adds an alias for a machine known by address, user and port, and shows the commands that authorize your key there.

• Detect Settings asks the machine (through ssh) for its scheduler, partitions, accounts, scratch, the Python that imports pDynamo and the QC programs, and fills the form.

• Remote folder, Python and Setup lines (shell lines run before Python: module load, sourcing the pDynamo environment, conda activate...).

• Scheduler: Direct (background process, for workstations) or SLURM (sbatch), with CPUs per job, and for SLURM the Partition (the refresh button lists them with sinfo), Account, Time limit, Memory and Extra #SBATCH lines.

• pDynamo and QC programs on that machine: the paths of ORCA, xTB and DFTB+ (empty when set by the setup lines) and of the pDynamo installation. With Use this computer's pDynamo Python files and parameters there, jobs run on a copy of that pDynamo folder with this computer's .py files and parameters on top, so local fixes and DYFF parameters go with the jobs while the installation there is not changed.

• Test Connection checks ssh, the folder, the scheduler, Python and pDynamo, and computes a real energy there; Save stores the machine.

EasyHybrid copies its own code to the machine at each submission, so the machine only needs pDynamo.