A Saturday afternoon alert: under-replicated partitions on the production Kafka cluster, well over the threshold. Status CRITICAL, replicas out of sync, risk of unavailability if a broker fails. The kind of page that makes you put down whatever you were holding.
Source: [Dev.to](https://dev.to/hugolesta/the-kafka-incident-that-was-just-a-certificate-and-the-operator-that-saved-mirrormaker-p94)