MakisH · Oct 27, 2026 · Oct 27, 2026 · Oct 27, 2026
diff --git a/02_virtualization_and_containers/docker_demo.md b/02_virtualization_and_containers/docker_demo.md
@@ -60,12 +60,12 @@ docker container attach tutorial
 - Contains Dockerfile
 
 ```Dockerfile
-FROM ubuntu:24.04
+FROM ubuntu:26.04
 
-RUN apt-get update -y && apt install -y neofetch
+RUN apt-get update -y && apt install -y fastfetch
 WORKDIR /app
 COPY testfile .
-CMD ["neofetch"]
+CMD ["fastfetch"]
 ```
 
 - `docker buildx build --tag testimage .`

diff --git a/02_virtualization_and_containers/docker_slides.md b/02_virtualization_and_containers/docker_slides.md
@@ -57,7 +57,7 @@ slideOptions:
 ## Container Solutions
 
 - Plenty of different container formats
-    - [lxc/lxd](https://linuxcontainers.org/), [Docker](https://www.docker.com/), [podman](https://podman.io/), [Apptainer](https://apptainer.org/), [Sarus](https://user.cscs.ch/tools/containers/sarus/)...
+    - [lxc/lxd](https://linuxcontainers.org/), [Docker](https://www.docker.com/), [podman](https://podman.io/), [Apptainer](https://apptainer.org/), ...
 - Different solutions with different strengths due to different use cases
     - Working on the (Super-)Userspace
     - Direct access to hardware vs. encapsulation
@@ -126,7 +126,7 @@ slideOptions:
     - Option 2: Be member of group `docker` (=makes you root), expected by some applications (e.g. `act`)
 - Alternatives:
     - [Rootless mode](https://docs.docker.com/engine/security/rootless/)
-    - Run Docker in a VM for better isolation
+    - Run Docker in a VM for better isolation ([Docker Sandboxes](https://www.docker.com/products/docker-sandboxes/))
 - Check [security notes](https://docs.docker.com/engine/security/)
 
 ---
@@ -211,12 +211,12 @@ Details available in [`docker_demo.md`](https://github.com/Simulation-Software-E
 ## Dockerfile Example
 
 ```Dockerfile
-FROM ubuntu:24.04
+FROM ubuntu:26.04
 
-RUN apt update -y && apt install -y neofetch
+RUN apt update -y && apt install -y fastfetch
 WORKDIR /app
 COPY testfile .
-CMD ["neofetch"]
+CMD ["fastfetch"]
 ```
 
 ---
@@ -238,6 +238,15 @@ Details available in [`docker_demo.md`](https://github.com/Simulation-Software-E
 
 ---
 
+## Making Images Smaller
+
+- Base image: `alpine` instead of `ubuntu`
+- Remove APT cache: `rm -rf /var/lib/apt/lists/*`
+- Remove intermediate build files (`*.o`)
+- Nice disk usage utility: [ncdu](https://en.wikipedia.org/wiki/Ncdu)
+
+---
+
 ## Advanced Topics
 
 - User ID mapping

diff --git a/02_virtualization_and_containers/singularity_demo.md b/02_virtualization_and_containers/singularity_demo.md
@@ -7,7 +7,7 @@
 - `apptainer shell precice_latest.sif`
     - Run shell in container
     - `whoami` will show same user as I am on the computer
-- `apptainer exec precice_latest.sif precice-tools --version`
+- `apptainer exec precice_latest.sif precice-version`
     - Run command in container
 - Show the mounted filesystems and hardware access.
 - Show that we cannot run things as root.
@@ -30,7 +30,7 @@
     export PATH=/usr/games:$PATH
 
     %runscript
-    precice-tools --version | cowsay | lolcat
+    precice-version | cowsay | lolcat
     ```
 
 - Show file `lolcow.def` content

diff --git a/02_virtualization_and_containers/singularity_slides.md b/02_virtualization_and_containers/singularity_slides.md
@@ -125,7 +125,7 @@ Details available in [`singularity_demo.md`](https://github.com/Simulation-Softw
 
 ```Singularity
 BootStrap: docker
-From: ubuntu:22.04
+From: ubuntu:26.04
 
 %post
    apt-get -y update
@@ -167,7 +167,7 @@ Details available in [`singularity_demo.md`](https://github.com/Simulation-Softw
 - Special container format for scientific computing
 - Immutable containers in a single file
 - Prefers integration over isolation
-- Other solutions: [Sarus](https://user.cscs.ch/tools/containers/sarus/), [Charliecloud](https://charliecloud.io/latest/index.html)
+- Other solutions: [Sarus](https://sarus.readthedocs.io/), [Charliecloud](https://charliecloud.io/)
 
 ---
 
@@ -176,4 +176,3 @@ Details available in [`singularity_demo.md`](https://github.com/Simulation-Softw
 - [Apptainer user guide](https://apptainer.org/docs/user/latest/index.html)
 - [Singularity User Guide](https://docs.sylabs.io/guides/main/user-guide/)
 - [Singularity Cloud](https://cloud.sylabs.io/library)
-- [Sarus](https://user.cscs.ch/tools/containers/sarus/)
diff --git a/02_virtualization_and_containers/vagrant_demo.md b/02_virtualization_and_containers/vagrant_demo.md
@@ -3,7 +3,7 @@
 ## Demo: Create VM based on a base Ubuntu box
 
 - Create a working directory and enter it.
-- `vagrant init bento/ubuntu-24.04` creates a base `Vagrantfile`.
+- `vagrant init bento/ubuntu-26.04` creates a base `Vagrantfile`.
 - `vagrant up` Creates `Vagrantfile`. This file can be put in version control.
 - Download and set up VM.
 - Will also start VM
@@ -27,7 +27,7 @@
 
     ```ruby
     Vagrant.configure("2") do |config|
-        config.vm.box = "bento/ubuntu-24.04"
+        config.vm.box = "bento/ubuntu-26.04"
         config.vm.provision :shell, path: "bootstrap.sh"
 
         config.vm.provider "virtualbox" do |vb|
@@ -42,15 +42,15 @@
     !/usr/bin/env bash
 
     apt-get update
-    apt-get install -y neofetch vim
+    apt-get install -y fastfetch vim
     echo "export TEST_ENV_VAR=\"Hello SSE\"" >> .bashrc
     ```
 
     - Installs software and sets `TEST_ENV_VAR`
 - `vagrant up`: Create VM
     - Image should be prebuilt
 - `vagrant ssh`
-    - Call `neofetch`
+    - Call `fastfetch`
     - `echo $TEST_ENV_VAR` to show that variable is actually set.
 - `vagrant package --base "sse-first-step" --output sse-first-step.box`: Export VM
 - `sse-first-steps.box` can be uploaded to [Vagrant Cloud](https://app.vagrantup.com)

diff --git a/02_virtualization_and_containers/vagrant_slides.md b/02_virtualization_and_containers/vagrant_slides.md
@@ -80,9 +80,10 @@ slideOptions:
     - Creates `Vagrantfile` -> Text file (Git friendly)
 - `vagrant up`
     - Create VM and start it
-    - VM is stored in `${HOME}/.vagrant.d/boxes` (overruled by `VAGRANT_HOME`)
+    - VM is stored in `${HOME}/.vagrant.d/boxes`<br/> (overruled by `VAGRANT_HOME`)
 - `vagrant ssh`
     - Connect to VM via ssh
+    - Get an SSH configuration with `vagrant ssh-config`
 - `vagrant destroy`
     - Stops the virtual machine and removes its disk
 
@@ -126,15 +127,15 @@ Details available in [`vagrant_demo.md`](https://github.com/Simulation-Software-
 
     ```ruby
     Vagrant.configure("2") do |config|
-        config.vm.box = "bento/ubuntu-24.04"
-        config.vm.box_version = "202510.26.0"
+        config.vm.box = "bento/ubuntu-26.04"
+        config.vm.box_version = "202606.01.0"
     end
     ```
 
 - Alternative (creates the corresponding `Vagrantfile`):
 
     ```bash
-    vagrant init bento/ubuntu-24.04
+    vagrant init bento/ubuntu-26.04
     ```
 
 - Start VM with `vagrant up`
@@ -160,6 +161,7 @@ Details available in [`vagrant_demo.md`](https://github.com/Simulation-Software-
 ## Vagrant Cloud
 
 - Repository of premade boxes: [HashiCorp Cloud](https://portal.cloud.hashicorp.com/vagrant/discover)
+- **However:** This is now deprecated -> community hosting
 - Package a box:
 
     ```bash
@@ -174,8 +176,8 @@ Details available in [`vagrant_demo.md`](https://github.com/Simulation-Software-
 
 ## Demo: Own box
 
-- `bento/ubuntu-24.04`:
-    - [HashiCorp Cloud](https://portal.cloud.hashicorp.com/vagrant/discover/bento/ubuntu-24.04)
+- `bento/ubuntu-26.04`:
+    - [HashiCorp Cloud](https://portal.cloud.hashicorp.com/vagrant/discover/bento/ubuntu-26.04)
     - [GitHub](https://github.com/chef/bento)
 - `precice/precice-vm`:
     - [HashiCorp Cloud](https://portal.cloud.hashicorp.com/vagrant/discover/precice/precice-vm)

diff --git a/02_virtualization_and_containers/virtualbox_slides.md b/02_virtualization_and_containers/virtualbox_slides.md
@@ -86,14 +86,14 @@ slideOptions:
 
 - VirtualBox runs both on x86 and ARM
 - ARM hosts need ARM VMs (no emulation)
-- Linux support limited/recent (e.g., Ubuntu 25.10)
+- Linux support limited/recent (e.g., Ubuntu 26.04)
 - Emulation alternative (very slow): [UTM](https://mac.getutm.app/)
 
 ---
 
 ## Content of a VirtualBox Image Directory
 
-- `VM.vdi`: The virtual hard drive containing the Guest OS
+- `VM.vdi` / `VM.vmdk`: The virtual hard drive containing the Guest OS
 - `VM.vbox`: XML containing metadata and configuration information (RAM, network devices...)
 - `VM.vbox-prev`: Backup of previous settings
 - `Logs/`: Directory containing log files
@@ -105,10 +105,10 @@ slideOptions:
 
 - Software and drivers to improves Guest's performance
     - Better video support, shared clipboard, ...
-- Might need additional packages. On Ubuntu 24.04 (guest):
+- Might need additional packages. On Ubuntu 26.04 (guest):
 
     ```bash
-    sudo apt install virtualbox-guest-utils virtualbox-guest-x11
+    sudo apt install virtualbox-guest-utils
     ```
 
 ---