Unusual-tricky Troubleshooting Scenarios

Scenario: "Venice": Am I in a container?

Level: Medium

Type: Do

Access: Email

Description: Try and figure out if you are inside a container (like a Docker one for example) or inside a Virtual Machine (like in the other scenarios).

Test: This scenario doesn't have a test (hence also no "Check My Solution" either).

Time to Solve: 15 minutes.

Scenario: "Oaxaca": Close an Open File

Level: Medium

Type: Fix

Access: Email

Description: The file /home/admin/somefile is open for writing by some process. Close this file without killing the process.

Test: lsof /home/admin/somefile returns nothing.

Time to Solve: 15 minutes.

Scenario: "Paris": Where is my webserver?

Level: Medium

Type: Hack

Access: Email

Description: A developer put an important password on his webserver localhost:5000 . However, he can't find a way to recover it. This scenario is easy to to once you realize the one "trick".

Find the password and save it in /home/admin/mysolution , for example: echo "somepassword" > ~/mysolution

Scenario credit: PuppiestDoggo

Test: md5sum ~/mysolution returns d8bee9d7f830d5fb59b89e1e120cce8e

Time to Solve: 15 minutes.

Scenario: "Jakarta": it's always DNS.

Level: Hard

Type: Fix

Access: Public

Description: Can't ping google.com. It returns ping: google.com: Name or service not known. Expected is being able to resolve the hostname. (Note: currently the VMs can't ping outside so there's no automated check for the solution).

Test: ping google.com should return something like PING google.com (172.217.2.46) 56(84) bytes of data.

Time to Solve: 20 minutes.

Scenario: "Singara": Docker and Kubernetes web app not working.

Level: Hard

Type: Fix

Access: Email

Description: There's a k3s Kubernetes install you can access with kubectl. The Kubernetes YAML manifests under /home/admin have been applied. The objective is to access from the host the "webapp" web server deployed and find what message it serves (it's a name of a town or city btw). In order to pass the check, the webapp Docker container should not be run separately outside Kubernetes as a shortcut.

Test: curl localhost:8888 returns a value from the webapp deployed Kubernetes pod.

Time to Solve: 20 minutes.

Scenario: "Monaco": Disappearing Trick

Level: Hard

Type: Hack

Access: Email

Description: There is a web server on :5000 with a form. POSTing the correct form password into this web service will return a secret.

Save this secret provided by the web page (not the password you sent to it) to /home/admin/mysolution, for example: echo "SecretFromWebSite" > ~/mysolution

TIP: a developer worked on the web server code in this VM, using the same 'admin' account.

Scenario credit: PuppiestDoggo

Test: md5sum /home/admin/mysolution returns a250aa19f16dda6f9fcef286f035ec4b

Time to Solve: 30 minutes.