A key feature in OpenMOLE is the possibility to delegate the workload to a remote execution environment. Tasks in OpenMOLE have been designed so that the delegation a part of the workload to a remote environment is declarative.

Defining an execution Environment

You first need to define the environment(s) you want to use an authentication method. Then, the actual delegation of the task is noted by the keyword on followed by a defined Environment:
val env = LocalEnvironment(10)

val t1 = EmptyTask()
val t2 = EmptyTask()
val t3 = EmptyTask()

val mole = t1 -- (t2 on env) -- t3

You do not need to install anything or perform any kind of configuration on the target execution environment for OpenMOLE to work. It reuses the infrastructure in place. You will however be required to provide the authentication information in order for OpenMOLE to access the remote environment. At this point, just specify the credentials you're using to login to this environment outside of OpenMOLE. Voila! That's all you need to do to use your environment through OpenMOLE. In case you face authentication problems when targeting an environment through SSH, please refer to the troubleshooting page.

When no specific environment is specified for a task, or a group of tasks, they will be executed sequentially on your local machine.


The use of a batch environment is generally not suited for short tasks (less than a 1 minute for a cluster to less than 1 hour for a grid). In case your tasks are short you can group several executions. To group the execution by 100 in each job submitted to the environment, use the keyword by:
val mole = explo -< (t1 on env by 100)

Available environments

Multiple environments are available to delegate your workload, check the following sections: