Better Kubernetes job scheduling

As enterprises race to scale their infrastructure to handle increasing workloads, many find it’s time to migrate from Cron Jobs or Windows Task Scheduler. Containerization like Docker or Kubernetes are excellent ways to automate application deployment, scaling and management but lack sophisticated job scheduling.

Redwood’s RunMyJobs fills that gap.

The drawbacks of OS schedulers

When it comes to batch jobs and workload management, Cron Jobs and Windows Task Scheduler simply don’t integrate as cleanly with containers.

1. They aren’t natively built to understand container infrastructure.
2. They can’t scale up or down based on container resource usage.
3. They don’t have visibility into container performance or resource usage, making it difficult to troubleshoot scheduled jobs across containers.
4. They’re not designed to orchestrate multi-container jobs.
5. Schedulers may have more permissions than are needed for job execution, making them a potential security risk.

Kubernetes CronJob

Kubernetes CronJobs are a custom implementation of the traditional UNIX utility called “cron.” A cron job is a task that’s executed on a repeating, regular schedule. Cron schedules and executes tasks in UNIX and Linux systems via a command line utility called crontab. Due to Cron’s reliance on custom scripts for complex tasks, cron jobs are most suited to basic tasks like scheduling backups, report generation or sending emails.

A cron job has a few important limitations. Modifying a cron job applies changes to all the new jobs that run after the modification. Any job that runs before the modification is complete will run without the modification. It’s not easy to stage a cron job to execute without a manual deployment.

There are also certain circumstances where a job may not run, or it may run twice, without the correct syntax or an unset, default or incorrect value. The lack of reliability among default presets and complicated syntax require intense manual work, slowing down productivity. Any logging of cron job executions has to be done manually and intentionally.

Teams can run automated tasks on Kubernetes using a Kubernetes CronJob object with a config file, but they are still subject to the limitations of CronJobs itself.

Kubernetes and Windows Task Scheduler

Microsoft is one of the most common operating systems and application platforms across many organizations. Teams that run Docker or other containerized environments can configure job scheduling in Windows with Kubernetes. Windows can use Kubectl commands and behave similarly to Linux containers.

However, Windows Task Scheduler offers only basic scheduling capabilities and is designed primarily to run tasks on a local machine, not across platforms or IT environments. It is, therefore, not desirable for large teams and organizations.

Both CronJobs and Windows Task Scheduler have similar drawbacks. Both are siloed and point-based and are not designed to handle large-scale tasks across multiple servers.

Automating Kubernetes with a job scheduling automation tool

An advanced enterprise scheduling tool like Redwood’s RunMyJobs enables teams to simplify their container-based automation. RunMyJobs can automate what teams spin up in a Kubernetes cluster, node or kubelet.

RunMyJobs is an advanced automation and orchestration engine fully capable of working with Kubernetes. It has an object-oriented design that integrates with and natively understands Kubernetes CronJob objects, namespaces, pod names and metrics (e.g., cpu, i/o, ram utilization). It even understands native Kubernetes constructs like onfailure, restartpolicy, pod lifecycles, kubectl logs, spec.schedule, selectors and tools like busybox/minikube. It works across multiple cloud platforms (e.g. Amazon, Azure, Google and others) and delivers workload automation that orchestrates multiple microservices into a single end-to-end service for your enterprise and enterprise scheduler tools.