Hi, I have a question regarding the --host(file) option of mpirun. Whenever I try to fork a process on another node using Spawn(), I get the following message:
Verify that you have mapped the allocated resources properly using the --host specification. I understand this can be fixed by providing the hostnames which will be used either by --host or by using a hostfile containing the names and possibly the slots available. This may be an acceptable solution, if one wants to start the same process on several blades, but what about starting a parent process which then initiates different child processes on other blades? In this scenario mpirun initially does not need the information of which other blades exist, but is only supposed to start the parent process locally. Surely, there must be a way not to previously specify blades, but to load this information at runtime, especially in a changing landscape where nodes are added at runtime. Is there a way to avoid this --host option? I'm using the latest version of OpenMPI (1.2.3). Best regards, Murat
