Incident #409: The Failed Payments

Brittany: Morning everyone. Are we seeing these payment gateway timeouts in Seattle? Users are complaining that transactions fail intermittently.
Steve: I'm looking at the logs right now. There's a huge memory leak in the billing service, and it's starting to bloat the main server.
Tom: Wait, let's not jump to conclusions. I checked the timestamps, and the timeouts started right after the v2.4 replica deployment.
Brittany: Good catch, Tom. But look at this status code. We've got a 502 Bad Gateway on every single checkout request.
Steve: That must be the new load balancer. It could be dropping packets because of a header mismatch in the payload.
Tom: I'm not so sure. That mismatch might be a red herring. Let's trace the actual database transactions first.
Brittany: I agree with Tom. We shouldn't be swamped by surface errors. Let's narrow down the outlier requests.
Steve: But look at the CPU usage! It's gradually climbing to 100% on all nodes.
Tom: That's just background noise. Let's correlate the payment failures with the failover event from last night.
Brittany: Did we fail over successfully at midnight? I thought that process was humble and quiet.
Steve: Wait, I see something fishy in the audit trail. Someone changed the retry timeout limit.
Tom: That's it! That's our smoking gun. A junior dev updated the retry limit without telling anyone, causing a massive traffic storm.
Brittany: Unbelievable. Let's revert that change immediately and get back to deep work.

Read again and choose the right answer

What problem are the engineers investigating in the chat thread?

• Intermittent payment gateway timeouts in Seattle
• A complete database crash in London
• An email server failure in Austin

What does Steve initially blame for the issue?

• A junior developer's configuration change
• A memory leak bloating the main server
• An expired SSL certificate

What does Tom think about the header mismatch?

• It is the main smoking gun
• It might be a red herring
• It proves there is a hacker

What turns out to be the real smoking gun?

• A changed retry timeout limit by a junior dev
• A broken load balancer in Seattle
• An automated cleanup bot from last year

Sources: photo by Mikhail Nilov on Pexels