Kube-Saver

Motivation

• Scale down cluster nodes by scaling down Deployments, StatefulSet, CronJob, Hpa during non-business hours and save $$, but if you need to scale back the resources eventhough its a scaledown, don't worry, You will have a Custom Resource which will scale up all resources and wont scale down until next scaledown period.

Installation

• Install CRD

  kubectl apply -f https://raw.githubusercontent.com/maheshrayas/kube-saver/main/k8s/crds/crd.yaml

• Configure your rules in rules.yaml

• Install kube-saver operator

  kubectl apply -k k8s/

Examples

rules:
  # scale down deployment with name go-app-deployment-2 when current time/day not in uptime
  - id: rules-downscale-deployments
    uptime: Mon-Fri 09:00-17:00 Australia/Sydney
    jmespath: "metadata.name == 'go-app-deployment-2'" 
    resource:
      - Deployment # type of resource
    replicas: 0 # either set the replicas:0 or any number during nonuptime 
  # scale down all deployment, statefulset, cronjob, hpa in namespace kuber when current time/day not in uptime, in this case hpa will be set to 1 as the desired replicas is set as 0
  - id: rules-downscale-all-deployments-in-namespace
    uptime: Mon-Fri 09:00-17:00 Australia/Sydney
    jmespath: "metadata.name == 'kuber'" 
    resource:
      - Namespace # type of resource
    replicas: 0 # either set the replicas:0 or any number during nonuptime 
  # scale down all statefulset in namespace kuber when current time/day not in uptime
  - id: rules-downscale-all-statefulset
    uptime: Mon-Fri 09:00-17:00 Australia/Sydney
    jmespath: "metadata.name == 'statefulset_name'" 
    resource:
      - StatefulSet # type of resource
    replicas: 0 # either set the replicas:0 or any number during nonuptime 
  # disable all cronjob with the labels current time/day not in uptime
  - id: rules-disable-all-cronjob
    uptime: Mon-Fri 09:00-17:00 Australia/Sydney
    jmespath: "metadata.labels.app == 'some_random_app'" 
    resource:
      - cronjob # type of resource
  # set minReplicas of HPA to 1
  - id: rules-set-hpa
    uptime: Mon-Fri 09:00-17:00 Australia/Sydney
    jmespath: "metadata.labels.app == 'some_random_app'" 
    resource:
      - hpa # type of resource
    replicas:1
  # set replicas to 0 when the resources has label app:some_random_app but not service:some_random_service
  - id: combination-of-resources
    uptime: Mon-Fri 09:00-17:00 Australia/Sydney
    jmespath: "metadata.labels.app == 'some_random_app' && metadata.labels.service != 'some_random_service'" 
    resource:
      - Deployment # type of resource
      - Statefulset
    replicas:0

• Define uptime in Olson timezone format

More Examples: here

How can I upscale resouce during the downtime.?

kube-saver will automatically upscale the resoures to orignial number of replicas when the current time falls between the uptime configured in rules.yaml. But if you want to manually scale up single deployment/statefulset or all the deployment & stateulset resources in Namespace, you have following options and it won't be scaled down until next day downtime. Choose any of the option below:

• Configure upscaled.yaml and

  kubectl apply -f ./k8s/crds/upscaler.yaml
  

  Or

• Redeploy your deployment.

  Or

• Edit the uptime in rules.yaml and redeploy the operator

  kubectl apply -k k8s/

Tested

Kubernetes Provider	Tested
Google Kubernetes Engine	✅
KIND(no autoscaler)	✅