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Nymfe Linux workstations

The Nymfe* workstations are student workstations in the PC hall and in the Linux classrooms (A219, C121, C122, S405) running Debian 13.

During the semester, the workstations are operational on weekdays from 7 am to 8 pm. If a user is still logged in at 8 pm, the machine will not shut down until 10 pm. In particular, Nymfe001, Nymfe002, Nymfe003 and Nymfe100 (and, due to teaching requirements relating to GPUs, A219 as well) run non-stop (except for a reboot at 5 am).

Due to restricted access to the FI network, you can only connect remotely to the Nymfe* machines from the MU network (for example, via the Aisa machine). In addition to the usual remote access via SSH, you can, if necessary, also use remote access via VNC. When working remotely, however, please ensure you use resources considerately.

In addition to the ‘home’ and ‘data’ directories, you can use the local (and therefore faster)/var/tmp – but please use this space considerately and save your data in a subdirectory corresponding to your faculty login. Thanks to XFS deduplication, it usually has a greater actual capacity than the volume size. We clear this storage space at the end of the semester.

You can also access your Windows home directory.

You can also read about an unusual problem from some time ago that we resolved in connection with Nymfy, or about the installation of Musa*workstations in the former lecture theatre B011.

Room maps

The current layout and occupancy of workstations are shown on the room maps in the Faculty Administration. The application also displays information about monitors with free HDMI and USB-C video cables for connecting your own laptops.

Troubleshooting

See Problems logging in to computers (not only via SSH).

Changing the system language

Changing the language does not work via the GNOME graphical settings; instead, you need to change the environment variable `LANG`, which is set in the file `.bashrc ` when the account is created.

So, if you want to change the language to English, edit the following line:

export LANG=cs_CZ.UTF-8

to

export LANG=en_US.UTF-8

To apply the changes, you’ll need to log out and log back in to the graphical session.

If you find that support for a particular language is missing, please let us know at.

Controlling the X.Org graphical interface from another machine

Please note! This method only works for sessions using X.Org, and therefore does not work in the new default sessionGNOME, which uses Wayland. If you wish to usex2x, you must select a suitable session, e.g.GNOME on xorg.

Using x2x you can use your laptop (or any Linux workstation) to control another Nymfe machine (this can be a useful alternative to freestanding monitors):

  • log in to a graphical session on a Linux workstation that will serve as a ‘secondary display’
  • find out the display name viaecho $DISPLAY – most commonly this is:0, which we’ll assume from now on

  • From another machine, which will serve as the primary machine and via whose keyboard and mouse you will control the second machine, log in to Nymfe:

    notebook$ ssh -Y xlogin@nymfeNN
xlogin@nymfeNN$ x2x -to :0 -east

  • if everything goes well, the command will appear to freeze; if you then move the mouse to the “eastern” edge of the laptop screen, the cursor should switch to the secondary screen and you should be able to control the windows using both the mouse and keyboard of the laptop

You can also choose other positions based on the cardinal directions, but this may not always work. In particular, if your laptop uses the Unity interface,-west, and the most natural option,-north, cannot be used due to the presence of the Gnome Shell panes. With XMonad, or if you’re having problems with maximised windows, you may also need to use -struts. You may also encounter difficulties with copying – in which case, try using the middle mouse button. (No, it doesn’t seem possible to chain several Nymphs together transitively.)

Container support – Podman

The Podman tool is available on Nymfe’s Linux workstations. Further information can be found in the Aura/Arachne server documentation.

Due to limited space, please tidy up after yourself when you’ve finished your work and delete any terminated containers and images! This may be useful:

# check Podman disk usage
podman system df
# remove all unused data
podman system prune -a
# delete all Podman data if you will not need any (requires confirmation)
podman system reset
# recheck Podman disk usage
podman system df

Container data is stored in/var/tmp/containers/, but please also refer to the information regarding deletion at/var/tmp above.

Thanks to the translation layer atpodman-docker, you can also use the commanddocker. The translation layer does not apply to the commanddocker-compose!

GPU – A219, PC hall

The Nymfe3* machines in A219 and the Nymfe001–003 machines in the PC hall are equipped with Nvidia GeForce RTX 4060 Ti (16 GB) GPUs. Thanks tonvidia-container-toolkit, these can also be used in containers (see also the GPU and Podman documentation for Aura/Arachne or the overview of GPUs at FI).

In the event of errors in header files withnvcc, add the `gcc-12.2 ` module or specify `-std=c++17`.

Parameters

Nymfe1* (ASUS All-in-One)

  • Intel® Core™ i5-11500 hexa-core (12-thread) processor running at 2.7 GHz (Boost 4.6 GHz)
  • 16 GB DDR4 RAM
  • 512 GB NVMe SSD
  • 23.8”, 1920x1080 monitor

Nymfe5* (HP All-in-One)

  • Intel® Core™ i5-14500 14-core (20-thread) processor running at 2.6 GHz (Boost 5 GHz)
  • 32 GB DDR4 memory
  • 1 TB NVMe SSD
  • 23.8" 1920x1080 monitor

Other Nymfe models (desktops)

  • Intel® Core™ i5-8400 six-core (twelve-thread) processor running at 2.8 GHz (Boost 4.0 GHz)
  • 16 GB DDR4 RAM
  • 500 GB NVMe SSD

Origin of the name

In Greek and Roman mythology, nymphs are water, forest and mountain goddesses, similar to our fairies and water nymphs.

Vojtěch Zamarovský: Gods and Heroes of Ancient Myths