Skip to content

Exercise 3: The Flash Crash

Time: 30 min
Previous: Exercise 2: The Subterranean Divide
Next: Exercise 4: The Rising Tide

Exercise 3

Asian markets are melting down. The quants need a calculation engine now. You will provision a fully configured VM (disk, secondary volume, production network, SSH key, cloud-init, fixed IP) in one pass.

3.1 Confirm the OS image

Images - confirm your Exercise 2 cloud image is Active (for example official-images/sles16 or the Leap Micro image you uploaded).

Confirming the OS image

3.2 Create algo-trader-01

Virtual Machines → Create:

Field Value
Name algo-trader-01
Namespace prod
CPU 2
Memory 2 GiB
SSH Key prod/default

Labels → Add:

Key Value
stage prod

Do not click Create yet.

3.3 Volumes and network

Volumes tab:

  • Root volume: select your cloud image, size 5 GiB (the cached image's own virtual size is under 2 GiB, so 5 GiB leaves comfortable room). If you swapped in a different image, check Images for its real virtual size first — Longhorn/Harvester can't shrink a cloned volume below that figure, so sizing the root volume smaller than it leaves the PVC permanently Pending and the VM ErrorUnschedulable forever.
  • Add Volume → name market-data-vol, size 1 GiB

Networks tab:

Field Value
Network prod/service

3.4 Cloud-init and fixed IP

Advanced Options → Cloud Configuration:

  • User Data Template: prod/prod (if you created it), or paste equivalent user-data
  • Network Data:
version: 2
ethernets:
  eth0:
    addresses:
      - 192.168.122.50/24
    gateway4: 192.168.122.1
    nameservers:
      addresses:
        - 192.168.122.1

Note: eth0 is the confirmed interface name on the cached image this workshop uses (the kernel also exposes enp1s0 as an altname for the same NIC, but eth0 is the primary name netplan/cloud-init sees). Other images may name it differently — if the VM boots without the static address, check ip link in the web console and adjust.

Node Scheduling (optional): run on nodes matching label stage=prod only if you labeled hosts; otherwise leave default (any node).

Provisioning the VM

Click Create. Wait until the VM is Running and shows an IP.

3.5 Web console and SSH

Opening the web console

  1. Open the VM → Console and confirm login / cloud-init finished.
  2. From the KVM host:
ssh -o StrictHostKeyChecking=no sles@192.168.122.50
# or the default user for your image
hostname
exit

Check your work: /opt/suse-virt-workshop/checks/check-exercise-3.sh.

Next: Exercise 4: The Rising Tide