Thomas Zeiser

Some comments by Thomas Zeiser about HPC@RRZE and other things


CFX-11.0SP1 and Windows CCS

According to Ansys, CFX-11 is not supported on Windows CCS. According to Microsoft, running CFX-11 on Windows CCS is no problem at all …

When we first tried some months ago on our small Windows CCS test cluster, we suffered from very strange error messages complaining about wrong paths, etc. even if only the GUIs were started on the terminal server (login node). Thus, we gave up again quite soon as diving into all details did not seem to be worth the effort.

I now tried again with a fresh installation of ANSYS/CFX-11 on our Windows CCS headnode – and what a surprise, no error messages any more.

At least for the CFX solver itself, it seems not to be a problem if UNC paths are listed in ...\ANSYS Inc\v110\CFX\conf\hosts.ccl for the compute nodes – although the CFX documentation mentions that UNC paths do not work for the CFX solver.

The default settings in ...\ANSYS Inc\v110\CFX\ are a bit strange – we do not have a \\headnode\cfxworkdir\ directory where everyone is allowed to write and it also seems to be a bad idea to always use just stdout and stderr for the output files …, thus, I locally made the following changes in on the shared directory of the CCS headnode:

  my $workingdirectory='//'.$hostname.'/ccsshare/'.$ENV{USERNAME};
  my $stdoutfile=$workingdirectory.'/stdout.%CCP_JOBID%.txt';
  my $stderrfile=$workingdirectory.'/stderr.%CCP_JOBID%.txt';

Now all output first of all goes into the user’s own shared directory, and second, the stdout/stderr files get the job-ID appended (and the suffix txt so that they are automatically opened with a text editor).

Initial tests look fine – let’s see what the users say.

Microsoft campus day with a special focus on Windows-Compute-Cluster (CCS)

Microsoft campus day with a special focus on Windows-Compute-Cluster (CCS)
Since some time, the HPC group at RRZE operates a small Windows Compute Cluster (cf.

Up-to-now only very little interest among our “normal” HPC users was observed. Therefore, a Microsoft campus day with special focus on Windows CCS is organized on January 17th at the Faculty of Economics, see for more details