Troubleshoot Taskers

Troubleshooting TASKERS on UNIX using rsh

If you cannot connect taskers to a server, check your license file with rlmstat. The total number of taskers you can connect to VOV servers is limited by the license.

To start a tasker on a remote machine, vovtaskermgr uses rsh as determined by vovrsh. However, a problem with your account setup can prevent remote taskers from starting. The following tests check if your account is setup to run rsh correctly:
  • % rsh hostname date

    This test should give you the date without asking for a password and without any other message. If a password is required, adjust the .rhosts file in your home directory. If any extra message is displayed, consider making the appropriate changes in your .cshrc file to eliminate them.

  • % rsh hostname vovarch

    This test should give you the platform name for the remote host, nothing else. If this message does not appear, verify that your .cshrc file is sourcing the .vovrc file, even for non-interactive shells. (A common trick in .cshrc design is to exit early when it is discovered, by testing for existence of the variable $prompt, that the shell is non-interactive. If the exit keyword exists in your script, move the sourcing of .vovrc before it.)

  • % rsh hostname

    (A login message appears at this point.)

    % vovtasker 

    (The usage message from vovtasker appears.)

    If this test succeeds and the previous test does not, then your PATH variable is incorrectly set in .login, while it is more appropriate to set it in the .cshrc file. You must correct this error before you can use VOV effectively.

  • % vovtaskermgr TEST host1 

    This tests if rsh works for a list of selected hosts. A host can pass this test and still not qualify as a tasker. This can happen, for instance, if the host does not mount the file system where the project data are stored.

  • % vovtaskermgr START -slow

    This shows in detail how taskers are started. The verbose output may help you debug the problem with starting taskers.

Troubleshooting TASKERS on UNIX using ssh

Many organizations are now switching to SSH for security reasons. If you also want to use SSH instead of RSH you need to do the following:
% vovsshsetup
Then in the taskers.tcl file, use the option -rshcmd ssh:
vtk_tasker_set_default -rshcmd "ssh"  
Now do the tests to see the rest of the setup:
% ssh hostname date
% ssh hostname vovarch