Scenario

A CronJob named cleanup in the ops namespace is failing to trigger as expected. It has an incorrect schedule, relies on the default timezone (which may not match the server), and retains too many completed jobs, cluttering the history.

Task

Fix the cleanup CronJob so that validation confirms it triggers exactly once per minute. Update the schedule to * * * * *, set the timezone to Etc/UTC, and ensure only the most recent successful run is retained.

Example

Current Status (Failing):

NAME      SCHEDULE    SUSPEND   ACTIVE   LAST SCHEDULE   AGE
cleanup   0 0 1 1 *   False     0        <none>          5m

Target Status (Success):

NAME      SCHEDULE    SUSPEND   ACTIVE   LAST SCHEDULE   AGE
cleanup   * * * * *   False     0        10s             7m

Step 1: Check current CronJob configuration

kubectl get cronjob cleanup -n ops -o yaml

Observe the incorrect schedule (e.g., 0 0 1 1 * runs once a year), LAST SCHEDULE is <none>, missing timezone, and high history limit.

Step 2: Edit the CronJob

kubectl edit cronjob cleanup -n ops

Step 3: Update the schedule and settings

Locate the spec section and make these changes (do not modify image or args):

spec:
  schedule: "* * * * *"               # Runs every minute
  timeZone: "Etc/UTC"                 # Explicit UTC timezone
  successfulJobsHistoryLimit: 1       # Keep only 1 successful job
  jobTemplate:
    # ... (Keep existing template)

The schedule: "* * * * *" is standard cron syntax for "every minute". The timeZone: "Etc/UTC" ensures consistent scheduling regardless of node local time (critical for distributed systems). Reducing successfulJobsHistoryLimit from default 3 to 1 saves etcd storage.

Step 4: Verify the changes

kubectl get cronjob cleanup -n ops
kubectl get jobs -n ops -w

Wait up to 60 seconds. The SCHEDULE shows * * * * *, LAST SCHEDULE updates, and only 1 completed job is retained.