When a server is slow and the dashboard is vague, a dozen standard commands narrow the problem to CPU, memory, disk, network or a single process in about five minutes. This is the order we run them in and how we read each output.
A narrative of one on-call night on a subscription payments platform: the 01:40 page, a settlement job stuck on a lock, a provider returning timeouts that were actually successes, the decisions under pressure, and the blameless review that followed. Details changed, mistakes and lessons real.
A practical guide to blameless postmortems: how to build a timeline, measure impact, find contributing factors instead of a culprit, write action items that get done, and run the review meeting so people tell the truth.