NestJS - Task Scheduling - Prevent running the same Job in parallel in identical service instances in K8s
You need to use the .spec.concurrencyPolicy field in your Cron Job spec and set it to Forbid, to prevent concurrent runs of the same job.
See the Concurrency policy chapter in this k8s doc: https://kubernetes.io/docs/tasks/job/automated-tasks-with-cron-jobs/