Hello,

This is the SadServers bulletin, featuring new practical challenges to help you build and strengthen your Linux and DevOps skills.

It's been a bit over a month since the last newsletter and we have eight new scenarios for you (and several more coming up): 

New scenarios since the last newsletter:

• "Salzburg": The TLS key that still matches. Based on a real issue we had when we had to renew a specific SSL certificate while having many certs and keys and not knowing which one was the right one 🤷‍♂️.
• New AWS CLI scenarios. Based on Floci, a cloud emulator:
  • "Istanbul": Delete unattached AWS EBS volumes - A simple "FinOps" common challenge: delete unused volumes to save costs.
  • "Auckland": S3 delete & archive old backups - Another cost-saving task: delete old S3 objects and archive some to a cheaper S3 tier.
• FIX (Financial Information eXchange) is a common electronic protocol for trading. Alexpotato, a Staff DevOps Engineer who has worked in trading firms, created these financial scenarios based on his experience. These Medium to Hard scenarios can be solved with standard Bash parsing tools and scripting.
  • "Trade": FIX drop reconciliation
  • "Flip": algo symbol flips
  • "Pos": position manager down + reconcile
• "Dublin": registration queue overload (HTTP 429) - when a client sends more requests than a server can process, you can do things like: 1) ignore and drop the requests 2) enqueue the requests/messages so they can be processed later 3) add more consumers/processors and independently 3) let the client know (HTTP 429) the server is overwhelmed. In this scenario a Redis queue keeps growing and the web server replies with 429 until the queue length is acceptable.
• "Cork": The catalog won't open - Another realistic scenario based on experience. Use troubleshooting procedures to to figure out what broke this server and fix it.

Other news:

• We have created a new front-end for the scenarios and dashboard (It requires to re-authenticate because security). It has better navigation features and it solves some edge issues with the current one. It will help expand SadServers into bigger DevOps/SRE problems not limited to a VM shell. Try it out and let us know what you think. Also I swear it's not vibed-coded ;-) 
• Waterloo Rocketry reaches new heights with World's highest amateur liquid bi-propellant rocket. SadServers, another endeavour from Waterloo reaching new heights is happy to sponsor them 🚀
• We are about to reach one million scenario VMs created, since SadServers started 4 years ago 😮.

 

If your company is interviewing for Linux/DevOps/SRE positions, or you want your team to practice incident response, you may be interested in our Business solutions, contact us for any questions.

Thanks,

Fernando Duran
SadServers Founder

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