HG FAQ

If you cannot get the setup to work on your own hardware, you can carry out the assignments in the Huygens terminal rooms.

HG00.029 is available for the course in the first session (TAs and teacher can be found there) and HG02.053 is also available in the afternoon session.

The latter terminal room is interesting too, because you may be able to reach these machines from the Linux login server, lilo.science.ru.nl, as long as they have not been turned off. You can ssh to hg053pcXX (replace XX by the number of the machine you have used) from Lilo with your science credentials.

The machines do not run docker but you can still use Docker images using podman. Until the package podman-docker has been installed by default, you simply have to replace docker by podman when following instructions. It should work fine, and we have tested things, but let us know if you see problems that you cannot explain, there could be a minor glitch due to this alternative system.

There is one problem: Podman runs as user, storing images and containers in your home directory, but the Docker images we use are too large to be stored there - this will result in errors when following the instructions of the course. The solution is to create your own directory on the machines local disk, that is available under /scratch, and then link that to the location where podman expects its data:

mkdir /scratch/$USER
mkdir -p $HOME/.local/share/containers
mv $HOME/.local/share/containers /scratch/$USER
ln -s /scratch/$USER/containers $HOME/.local/share

Now, you can use the commands to pull the image and create a container using podman instead of docker as follows:

podman pull docker.io/rubigdata/redbad
podman create --name redbad -e HADOOP_USER_NAME=sXXXXXX -it rubigdata/redbad 
podman start redbad

Run a shell to give commands using the container you just started:

podman exec -it redbad /bin/bash