There are several topics below, please scan the whole list to see if one or more affects you.

Duo authentication replaces MToken

We, along with ITS, have switched our two-factor authentication from RSA Tokens (MToken) to Duo. For a short time, we will make available a host called flux-login-rsa.arc-ts.umich.edu that will continue to accept the MToken. Please register for Duo as soon as possible and stop any sessions on the flux-login-rsa host once you have successfully logged into the Duo login hosts. For more information and to enroll with Duo, please visit the ITS Duo web page.

Problem with X forwarding

We have been seeing some errors when trying to use X forwarding to view GUI applications back to people’s own computers. The errors have been either about a ‘buffer’ or about a library called ‘swrast’. The rest of the text varies widely among applications. These problems began occurring prior to the maintenance and persist with the new operating system and software versions.  The error is not being generated on Flux; rather, it is being generated on the computer that would display the application window.  We do not have fixes for this at this time.  We recommend that, if you need a GUI interface, you use either ARC Connect or if you were using the VNC, that method still works.

System and private modules no longer loaded

We are no longer loading a default compiler nor a default MPI when you login. If you see an error like

-bash: mpirun: command not found

that is why.

Many people were finding that they had to remove the default modules every time, and in some cases having those loaded was causing problems. If you had a privatemodules/default on the old system, that will not work, but you can set up something similar with the new, and that is also how you should get back the Intel compilers and OpenMPI by default, if you wish.

The module program changed to Lmod during the maintenance. As a consequence, the previous mechanism for loading a set of modules at login no longer works. We are also not loading modules for you at login.

Lmod enables you to load a set of modules at login by creating a saved set called ‘default’ (you can also create other sets with different names). This is different from the old default file.  Run something like the following commands on the login server (using the modules you would like in your default set) to create the Lmod defaults.

$ module purge
$ module load intel/16.0.3
$ module load openmpi/1.10.2/intel/16.0.3
$ module save

That will create a file called ~/.lmod.d/default that contains the information Lmod needs to load that complete set of modules.  If you then log out and log back in again, running

$ module list

will show the modules loaded.  Please see the Lmod transition page for more information.

Other module commands should mostly work as before. Please refer to the Managing Software with Lmod section of the Flux user guide for more information.

Ansys and CPLEX software moved to the Flux on-campus nodes

The license for all Ansys software – Ansys, Fluent, CFX, Maxwell, HFSS – has restrictions based on where the user is physically located, as does the CPLEX package. We have moved that software to the portion of Flux that is only accessible from computers on know UM campus networks and MWireless. You should change the host to which you log into from flux-login.arc-ts.umich.edu to flux-campus-login.arc-ts.umich.edu. This is following similar changes implemented in the College of Engineering over a year ago.

NOTE: You will also need to change the queue when submitting jobs to the campus-only nodes. You should have

#PBS -q flux-oncampus

In your PBS script to direct the job to the nodes that have the restricted software. That queue and those nodes are not accessible from the regular Flux login nodes, but the regular queues and nodes are accessible from the on-campus nodes.

Abaqus unavailable until further notice

We were unable to complete the installation of Abaqus due to problems with the installers. We will contact the vendor on Monday and will provide Abaqus as soon as we can.

VNC from inside PBS jobs has issues

The manual process for starting a VNC session seems to have an issue now that keeps it from running within a non-interactive batch job. There are three possible workarounds.

  1. Flux only (does not work on Armis): Use ARC Connect.
  2. Flux only (does not work on Armis): Use the vnc-start command. If you are in an interactive PBS job, just run vnc-start and use the connection information it prints. If you are submitting a non-interactive batch job, replace all of the existing VNC start-up commands with the following:
    vnc-start
    sleep ${PBS_WALLTIME}

    You will then need to run qpeek from the login node to get the VNC connection information after your job has started.

  3. Flux and Armis: Using an interactive batch job, follow the manual process for starting a VNC session but omit the -fg option from the vncserver command.

Rmpi is not currently available

There is a configuration issue with Rmpi at the moment and it is not functioning. We are looking into this and hope to have it resolved soon early in the week of July 25.