Resources available

Requesting access

• Email math-helpdesk@umd.edu to request access.
• If you aren't listed as having a Math affiliation in the campus directory, you need to include who you are working with in Math.

Using the servers

• Connecting to the servers
  • If you are off campus, connect to the UMD GlobalProtect VPN first.
  • Use Secure shell access to connect to your preferred server from the table above.
  • Use SFTP to transfer files to/from the servers.
    • Windows - SCP/SFTP using Winscp
    • Mac - SFTP using Cyberduck
    • Linux - SFTP using the command line in a terminal
• Storage
  • For mathhpavw1202a, b, and c there is a significant amount of local storage that should be available to each user under /export/<username>.  This storage is local to each server meaning you can't see the storage on one from any of the others.  This local storage is not backed up and should be used as temporary space you need during your computations.  These servers also connect to a file server that provides a small amount of home space that is accessible from any TerpConnect server so it can be seen from all 3 of these servers as well as glue.umd.edu and login.math.umd.edu.
    • You can see how much space is left with the command below.
      • df -h
      • You should see something like the output below.  Look for the "/" entry which is the last one below and it has 1.7 TB free.
        • mathhpavw1202a:~$ df -h
          Filesystem                                 Size  Used Avail Use% Mounted on
          devtmpfs                                   377G     0  377G   0% /dev
          tmpfs                                      377G  512K  377G   1% /dev/shm
          tmpfs                                      377G  1.8G  376G   1% /run
          tmpfs                                      377G     0  377G   0% /sys/fs/cgroup
          /dev/mapper/rhel_mathhpavw1202a-root       7.0T  5.4T  1.7T  77% /
  • If you run out of quota in your home space which is on the file server, leverage the space mentioned above.
    • Quota management.
      • Check quota "fs examine ~<username>"
      • Check what is using the quota "du -h ~<username> > /tmp/<username>.usage"
      • Then look at the /tmp/<username>.usage file to see where the storage is being used.  It's typically in .cache or other dot file locations.
      • These locations can be moved to /export/<username>.
    • For example, if you are trying to install something like miniconda3, you can do the folllowing to leverage the local space in /export which will create a symbolic link to redirect anything written to your home space in ~<username>/miniconda3 to /export/<username>/miniconda3.  See issues below if you need assistance with this. 
      • ln -s /export/<username>/miniconda3 ~/miniconda3
    • Moving .cache.  All future data written to ~/.cache will be redirected to /export/<username>/.cache
      • mv ~/.cache /export/<username>
      • ln -s /export/<username>/.cache ~/.cache
• Long running jobs
  • For jobs that you think will run over 24 hours, don't use your home space.  Use the temporary /export/<username> directory to store input and output files.  The file server where your home space is located expires access every 24 hours for security reasons.
  • If you end your ssh session, anything you have running will terminate as well.  There are multiple ways to handle this but we recommend using "screen" or "tmux". 
    • Here is a guide for using "screen".
    • Here is a guide for using "tmux".
• Access software
  • If you run a command to execute a piece of software and the command isn't found, you can use the module command to see if the software is available using that method.

Issues

Contact math-helpdesk@umd.edu, call 301-405-1634, or stop by Martin Hall 0123 for assistance including requests for any software installations.

UMD HPC

Zaratan is available, but Math has not made any investments. There are some free allocation options available. https://hpcc.umd.edu/