Unusual-tricky Troubleshooting Scenarios

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Unusual-tricky

Scenarios that are unrealistic or tricky/weird

#	Name	Level	Time	Type
1	"Venice": Am I in a container?	Medium	15 m	Do	"Venice": Am I in a container? 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.
2	"Oaxaca": Close an Open File	Medium	15 m	Fix	"Oaxaca": Close an Open File 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.
3	"Paris": Where is my webserver?	Medium	15 m	Hack	"Paris": Where is my webserver? 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.
4	"Jakarta": it's always DNS.	Hard	20 m	Fix No Registration	"Jakarta": it's always DNS. 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. Paid accounts can ping outside and check the solution with `./agent/check.sh` 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.
5	"Singara": Docker and Kubernetes web app not working.	Hard	20 m	Fix	"Singara": Docker and Kubernetes web app not working. 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. Get the webapp Deployment in the web namespace to a Running pod that serves its HTTP response (a town/city name). Running the image with host Docker alone is not enough to pass the check. TIP: You can use `k` as an alias for `kubectl`, and it has autocomplete enabled. Test: `curl localhost:8888` returns a value from the webapp deployed Kubernetes pod. The "Check My Solution" button runs the script /home/admin/agent/check.sh, which you can see and execute. Time to Solve: 20 minutes.
6	"Monaco": Disappearing Trick	Hard	30 m	Hack	"Monaco": Disappearing Trick 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.

Unusual-tricky Troubleshooting Scenarios

Unusual-tricky

Scenarios that are unrealistic or tricky/weird

"Venice": Am I in a container?

"Oaxaca": Close an Open File

"Paris": Where is my webserver?

"Jakarta": it's always DNS.

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

"Monaco": Disappearing Trick

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