Known Issues

Weird keyboard layout inside the VM

If you are “inside” the appliance window, you might find that the keyboard mapping is weird. This is probably a QWERTZ vs QWERTY issue. Example: You hit z and get a y. The VM adopts a US keyboard mapping by default which might cause problems in case your keyboard is mapped for another country. There are two ways to change the keyboard mapping: permanently, or just for the current session.

Change keyboard mapping permanently

On the VM shell, execute:

$ sudo dpkg-reconfigure keyboard-configuration

Walk through the menu: in most cases, you can just confirm the default settings by hitting Enter. However, carefully choose the adequate country in the sub-menu Country of origin for the keyboard.

Change keyboard mapping just for current session

For this, you need to install console-data:

$ sudo apt-get install console-data

from the VM shell. During the installation process, you will be able to choose an appropriate keyboard layout: choose Select keymap from arch list, then continue according to your keyboard layout (typically qwertz or qwerty) and country.

In case you already have console-data installed, just execute:

$ sudo dpkg-reconfigure console-data

instead, and follow the same procedure.

System Python vs. conda

The VM contains two Python distributions: Python 2.7 that comes with Debian 9 (used by BALTRAD and Radx), and a Python 3.6 conda environment (used by Py-ART, wradlib, and PyTMatrix). We tried to minimize conflicts between the two Python environments. Please see Quick start on how to launch jupyter notebooks in the different Python environments.

Still, a problem might occur in case a the metadata of a jupyter notebook refers to Python 2, although the notebook would require to be run from within the conda Python 3.6 environment. If your notebook fails and shows an active Python 2 kernel, please switch manually to a Python 3 kernal using the notebooks GUI. Alternatively, you can edit the notebooks metadata to refer to Python 3, and then restart the notebook.

Using conda

In order to avoid conflicts with the system Python, we did not add conda to the PATH environment variable. If you want to execute conda commands on the VM, you need to make use of the environment variable $CONDA_DIR which points to conda’s installation directory. Instead of e.g. activating the conda environment openradar via

$ source activate openradar

please use

$ source $CONDA_DIR/bin/activate openradar

32-bit vs. 64-bit

We do no longer support 32-bit environments. If you have a 32-bit host environment, the 64-bit will fail. That applies both for the image downloads and for builts from source. Still, you might find some guidance here on how to build a 32-bit image yourself.

When you import the image to VirtualBox, check the Appliance Settings: Make sure that “Guest OS Type” is “Debain (64bit)”.

Enabling virtualization

Disabled hardware virtualization features on the host system can lead to weird error messages (such as “VT-x/AMD-V hardware acceleration is not available on your system”). This particularly applies to Windows, but virtualization support can also be disabled on Linux hosts. The way how to enable virtualization support depends on the system. Please read this article on how the issue might be adressed on Windows hosts - usually you need to change the BIOS settings to enable virtualization support.

Cleaning up after removing a VM

If you want to remove an appliance from your computer, you can use the VirtualBox manager, select the appliance, and click “Remove”.

However, in some cases, VirtualBox might not remove all the corresponding VM files from your file system. In that case you need to do that manually. Under File > Preferences, find your “Default Machine Folder”. Navigate there and delete the remaining directories that correspond to the appliance you want to remove.