ParaStation MPI is also able to start up serial tasks, which are not counted within the process management. Those tasks are called administrative tasks. Thus, an arbitrarily number of tasks can be placed on a particular node, even if there are already parallel tasks spawned.
In order to start an administrative task on a node, execute
# pssh -h
This will run the command program on the node
nodename providing it the arguments
By default, only root is allowed to run this type of
tasks, as this may burden unexpected load onto a compute node.
To enable other users, there id must be added to the
adminuser list or the user's group must be
added to the
admingroup list. For details,
Currently, there is no way to change the user id except for root. There is no way to provide a password. The data is not encrypted while transfered across the network.
In addition to pssh, the
mpiexec command may be used to run one or
more administrative tasks in parallel.
Use the option
--admin to do so:
# mpiexec -np 1 --admin --hosts
nodename may be a particular
hostname or a (command separated) list of hosts.