Linux World Cup - 2023

spoiler alert!

Top 3

Position Competitor Alias Total Time to Solve
1 aretea 42 mins 13 secs
2 & 3 martbhell 47 mins 12 secs
2 & 3 mgubenko 47 mins 21 secs

The challenges

Recording from this event


I was best! Took 21mins 28seconds

Still 21 minutes was quite a beast!

I spent some time in advance here learning about rabbitmq. But sure, during these 21mins I was reading rabbitmqctl guide

I had some experience with rabbitmq from before so the concepts weren't that far away.


Also best. 3mins 46seconds - link to the asciinema recording

  • I kept looking inside .bash_history but that did not help at all.
  • Finally looked in git status`` even though from initialls -la` I could have seen it.


Quite a lot slower. 11m 26secs vs 2m32 for winner.

Winner: Used some awk (typed it in without copying, so could have prepared a bit better :) to parse. Very elegantly and small compared to .. my python.

I wrote some python to read it. Had it prepared. But still managed to introduce typos and indentation issues. Could have prepared the csv reader much more in advance. But OK, I wanted a challenge under pressure. Keep forgetting that it's all strings.. vim recover file.

While typing figured out how I wanted to solve it instead of thinking it through beforehand.


Also slower. 3mins 14s vs 1min 31s.

Winner: jq . the_json and printed top 10 lines and took the first one??


  • prepared some python to read json
  • very very slowly updated the python to read the json and get to what I needed
  • introduced and fixed bugs in the python as I went along :D


Ridonc. I took 7mins 18 vs 31s of winner.

Hahha. So this challenge was a port knocker. The fastest just nmapped all ports and then curled to localhost!

Whereas I:

  • downloaded some
  • messed around inside the source code..
  • guessed that range would be in 56400 because that's where..
  • then tried to hack the system to get the config of the program that was handling the knocking (knockd)
  • tried to read the ansible tmp files to get it
  • tried reading log files to find it
  • went back to and ran it with -b
  • ...

All in all

Great fun, warmly recommend fixing some sad servers :)