Naisjob¶

A Naisjob is very similar to a NAIS Application, except that it only runs once by default. It is built on the Kubernetes Job and CronJob resources. A CronJob runs Jobs on a time-based schedule, as denoted in .spec.schedule.

Restart policies

Naisjobs have restart policies set to "Never", and it is currently not possible to set the restart policy of a Naisjob directly. It is possible to achieve automatic restarts on failure by using startup probes however, though this requires the Pod to expose an HTTP endpoint to answer the probe.

Below you can find a minimal Naisjob example with a schedule for running a Job every minute. If you don't need to have a recurring Naisjob, remove the schedule field from the configuration.

apiVersion: nais.io/v1
kind: Naisjob
metadata:
  labels:
    team: myteam
  name: myjob
  namespace: myteam
spec:
  image: europe-north1-docker.pkg.dev/[mgmt-id]/[team-name]/[image-name]:tag
  schedule: "*/1 * * * *"

Behind the scenes, when you make a Naisjob, Kubernetes makes a bunch of different resources for you. Naisjob is one resource that has been defined by the NAIS team. When you deploy a Naisjob with spec.schedule, Kubernetes will create a CronJob for you. A Cronjob is a Kubernetes native resource. When the Cronjob-schedule triggers, Kubernetes will create a Job-ressource, which creates a Pod-resource. The Pod is what actually runs your code.

If you make a Naisjob without schedule, Kubernetes will create a Job-resource directly, which will create a Pod-resource.

Below you can see some of the resources the Naisjob tiltak-okonomi-avstemming creates.

$ kubectl tree naisjob tiltak-okonomi-avstemming
NAMESPACE     NAME                                        READY  REASON  AGE
arbeidsgiver  Naisjob/tiltak-okonomi-avstemming           -              109d
arbeidsgiver  ├─Job/tiltak-okonomi-avstemming             -              109d
arbeidsgiver  │ └─Pod/tiltak-okonomi-avstemming-brb7c     True           12d

Re-run Naisjob¶

If you don't want to run your job at a schedule, but still want to re-run your Naisjob:

kubectl patch naisjob <name> --type json -p='[{"op": "remove", "path": "/status/synchronizationHash"}]'

Applying your Naisjob to Kubernetes¶

You can deploy your Naisjob just as you would deploy your Application using NAIS deploy.

Shutting down extra containers¶

Due to the nature of NAIS, your Naisjob might end up having a few sidecars. Since a sidecar typically has little to no logic to look at sibling containers, these would normally not turn off once your app completes. As a result, the Naisjob would continue running indefinitely unless some entity from above sorts it out. To remediate this, an operator named HAHAHA has been created to run in every cluster and observe every Naisjob. Once the "main" container in a Naisjob completes, HAHAHA will shut down the surrounding sidecars and thus make the Naisjob run to completion.

You can look at what HAHAHA has done to complete your Naisjob by running kubectl describe pod my-naisjob-3f91a0 and viewing the Events section.

My Naisjob hasn't completed

If you see events from HAHAHA but your Naisjob didn't complete, we'd be happy if you could tell us in the #nais channel on Slack.

I want to manually shut down the sidecars to make the Naisjob complete

Here's some legacy documentation on how to shut down most sidecars, in case HAHAHA didn't do its job fully.

Linkerd¶

Linkerd exposes an endpoint to shut itself down.

curl -X POST http://127.0.0.1:4191/shutdown

This is done from inside your pod-container.

CloudSQL-proxy sidecar¶

CloudSQL-proxy sidecar does not support turning off remotely.

It can be shut down by running exec into the container.

kubectl exec yourpod-12345 -c cloudsql-proxy -- kill -s INT 1

Securelogs¶

Securelogs runs on Fluentd, and Fluentd exposes an endpoint to shut itself down.

curl http://127.0.0.1:24444/api/processes.killWorkers

This is done from inside your pod-container.

Additionally, Securelogs runs a second sidecar called secure-logs-configmap-reload. This can be shut down by running exec into the container.

kubectl exec yourpod-12345 -c secure-logs-configmap-reload -- /bin/killall configmap-reload

Vault sidecar¶

Vault sidecar does not support turning off remotely.

It can be shut down by running exec into the container.

kubectl exec yourpod-12345 -c vks-sidecar -- /bin/kill -s INT 1

Troubleshooting / FAQ¶

My NaisJob doesn't want to start any scheduled Jobs¶

Answer

Sometimes, if the defined schedule attempts to start Jobs frequently without succeeding, Kubernetes will eventually stop attempting to start the Job.

You might see the following event or message for the related CronJob (kubectl describe cronjob <name>):

Cannot determine if job needs to be started: too many missed start time (> 100). Set or decrease .spec.startingDeadlineSeconds or check clock skew

Currently, the only way to fix this is to delete the CronJob and NaisJob, and then re-apply or -deploy the NaisJob:

kubectl delete cronjob <name>
kubectl delete naisjob <name>
kubectl apply -f <path-to-naisjob.yaml>

How do I force run my scheduled job¶

Answer

Run the following command to create a ad-hoc job based on your cronjob:

kubectl create job --namespace=<mynamespace> --from=cronjobs/<naisjobname> <newname>

Last update: 2023-05-15
Created: 2021-06-07