What caused the sudden spike in error rates for GovTech's Singpass authentication service last week?

Introduction

The sudden spike in error rates for GovTech's Singpass authentication service last week is a critical issue that demands immediate attention and thorough analysis. As we delve into this problem, we'll employ a systematic approach to identify, validate, and address the root cause while considering both short-term fixes and long-term implications for the service.

Step 1

Clarifying Questions (3 minutes)

• Looking at the timing, I'm thinking this could be related to a recent system update. Has there been any significant changes or deployments to the Singpass system in the past week?

Why it matters: Recent changes often correlate with sudden performance issues. Expected answer: Yes, there was a minor security patch deployed. Impact on approach: If confirmed, we'd focus on the patch's impact and potential rollback.

• Considering the nature of authentication services, I'm curious about the specific type of errors we're seeing. Are these primarily timeouts, invalid credentials, or system unavailability errors?

Why it matters: Different error types point to different root causes. Expected answer: Mostly timeout errors. Impact on approach: This would lead us to investigate network or server capacity issues.

• Given that Singpass is a critical government service, I'm wondering about the scale of the impact. What percentage of authentication attempts are failing compared to the baseline?

Why it matters: Helps quantify the severity and urgency of the issue. Expected answer: Error rates have increased from 0.1% to 2%. Impact on approach: This significant increase would prioritize our investigation and response.

• Thinking about potential external factors, have there been any unusual spikes in usage or changes in user behavior recently?

Why it matters: External events can sometimes trigger unexpected system behavior. Expected answer: No significant changes in overall usage patterns. Impact on approach: This would lead us to focus more on internal system issues rather than external factors.