test_nodes — test physical connections within a cluster.
test_nodes  [-np num] [-cnt count] [-map] [-type]
      Tests all or some physical (low level) connections within a cluster. Therefore the
      program is started on num nodes. After all
      processes came up correctly, each of them starts to send test packets to
      every other node of the cluster. For this purpose the PSP_IReceive(3) and PSP_ISend(3) calls of the ParaStation MPI PSPort library are used.
    
After every node has received data from any node (i.e. an all to all communication was executed), a success message is printed and test_nodes exits. Otherwise after a certain timeout a message concerning the current status about the tested connection is posted.
test_nodes will run as long as any connection between two tested nodes is unable to transport the test packets.
-np num
        Run the testing program on num
	    nodes.
	  
-cnt num
        Send num test packets at once
	    instead of only one.
	  
-map
        Don't print error messages but rather print a map with all working connections marked as 1 and all failed connections as 0.
-type
        Print the type of each connection used instead of
          packets send/received. Implies -map.