HPC/Support

Review the FAQ list

For frequently asked questions regarding the Carbon HPC system, review Frequently Asked Questions to find answers.

Compose a support request

If your question is not answered in the FAQ, Compose an email to our help desk, as follows:

Required information

• Choose an appropriate subject line, preferably after you typed and reviewed the body of your message.

  Do not merely hit "Reply" on a previous unrelated message - doing so might cause your request to get overlooked in a previous thread.

• Be as specific as possible in the body of your message. Include the following:
  • The command you were trying to run or the menu item you chose in a graphical user interface
  • The exact error message you get. Copy & Paste the message text, or take a screenshot and attach it to your mail.
  • The directory path and file name you were working on, if applicable.

    It is generally not necessary to include in your message copies of files that already reside on Carbon.

For issues with PBS jobs

For questions about PBS jobs, provide:

• the working directory of the job
• the name of the job file used
• the job number (for queued or running jobs)

Additions required for remote access issues

When you cannot log in to mega or a Carbon login node, provide the following:

• The hostname you ran the command on. It is often shown in the command prompt. (If the prompt shows localhost it is not specific enough – ask your local support person for help.)
• The hostname you're trying to reach.
• The username you use to connect.
• The software name and version you use to connect (e.g. SSH, VNC, or a browser).
• Your operating system and version.

If you use ssh or scp, repeat your command in verbose mode by supplying the "-v" option twice:

scp -v -v [… other options and arguments …]
ssh -v -v [… other options and arguments …]

Copy and Paste the possibly multi-page output into your request.

Test directory

We may ask you to prepare a test directory which has to contain only files required by your application for a standalone run or a single PBS job. This will help to diagnose your problem and confirm resolution, especially to diagnose subtle errors that are difficult to reproduce, such as where your application runs but does not fail outright.

Prepare the test directory at the same directory level as your troubled runs, and include:

• the PBS job file,
• input files,
• any local data files.
• If available, add a file with the expected (correct) output, but with a file name that's different from the one generated by the job, such as by adding .ref.

Submit

Before you submit a request:

• Make sure you included the error message that prompted your request.

Complete the following form submit your request: CNM HPC Support Request

Receiving support

When you get our support response:

• Carefully read it.
• Follow all instructions and answer all questions.
• For account- and password-related issues: it may take several hours for changes to take effect. If your initial attempt fails, wait at least that long before retrying.

Additional considerations

To help us diagnose a problem:

• Read How to Report Bugs Effectively, by Simon Tatham, programmer.
• For deeper reading, consider How To Ask Questions The Smart Way, by Eric S. Raymond, open source pioneer.