OpenShift - Scaling and Autoscaling - Part 4

 

Scaling and Autoscaling:

Horizontal scaling adds more machines into the system while vertical scaling add more resources to existing system.

#oc scale dc/name --replica=<number>

Monitoring the pod:

#oc adm top pods

#oc get events

Autoscaling:

It will increase the CPU and memory depends upon the requirement by automatically.

#oc autoscale dc/<name> --min=3 --max=6 --cpu-limit=60

List the information about the project:

#oc describe project projectname

Patching the Pod:

#oc patch dc/<name> -p '{"spec":{"template":{"spec":{"containers":{"image":"quay.io/existimage/newimage"}}}}}'

Secret and configMap:

Secrets is a encrypted data (Sensitive information)

configMap is a plain text (hostname, ceritificate)

Secret types:

1) Generic 

2) TLS (SSL)

3)docker-cfg

secret is using a base64 format encreption method.

Decode the secret file

#base64 --decode secretfile

List the secret

#oc get secret

#oc set env dc/mytest --from=secret/mytest-secret

Login into Pod:

#oc exec -it podname -- bash

#oc get pod -o yaml | grep -i scc

#oc get pod podname -o yaml | oc adm scc-subject-review -f -

#oc adm policy add-scc-to-user username

#oc adm policy remove-scc-to-uesr username

Templete is not found Error:

#oc login -u kubeadmin -p $(cat /usr/local/etc/kube-admin-password) https://api.example.com:6443

#oc edit projects.config.openshift.io 

Removed projectRequestTemplete & name parameter and place a empty {}