Lab 0 — Set up before class¶

Do this before Class 5, not during it. Installing Wireshark on Windows can need a reboot, and you do not want to spend lab time on it. ~15 minutes, once.

This one really is a before-class step

If you arrive with nothing installed, you will lose the first 20 minutes of a 2-hour lab. Get the three checkmarks below green at home.

1. Docker¶

Install Docker Desktop (Windows / macOS) or Docker Engine (Linux).

docker compose version

Checkpoint

Prints a version like Docker Compose version v2.x. If "command not found", Docker is not installed or not running — start Docker Desktop and try again.

2. Wireshark (with loopback capture)¶

Install from wireshark.org/download.

WindowsmacOSLinux

During install, let it install Npcap, and on the Npcap screen tick "Support loopback traffic capture". This is the box people miss — without it you cannot capture localhost, and that is the whole first exercise.

Already installed Wireshark without that option? Re-run the Npcap installer alone (download from npcap.com), and tick "Support loopback traffic capture" this time. Reboot after.

The installer sets up the capture helper (ChmodBPF) for you. If prompted, allow it and reboot. Your loopback interface is Loopback: lo0.

sudo apt install wireshark      # choose "Yes" to let non-root users capture
sudo usermod -aG wireshark $USER

Log out and back in. Your loopback interface is lo.

Checkpoint

Open Wireshark. In the interface list you can see a loopback interface (lo0 / lo / Npcap Loopback Adapter) and double-clicking it starts a live capture without an error.

3. NotesApp¶

Use your clone from Class 2. Lost it?

git clone git@github.com:<your-username>/NoteApp.git notesapp
cd notesapp
docker compose up -d

Checkpoint

http://localhost:8080 shows the NotesApp login page. (Then docker compose down until class if you like — your data lives in a volume and is kept.)

All three green? You are ready. Start with Lab 1 — HTTPS in class.