You will need to push your image to a registry. If you have not done so, use the following commands to tag and push the images:
$ docker image tag pizzastore gcr.io/ody-offer-letter/pizzastore
$ docker push gcr.io/ody-offer-letter/pizzastore
You can deploy all your apps by running the below bash command:
./kubectl-apply.sh
Use these commands to find your application's IP addresses:
$ kubectl get svc pizzastore -n pizza-store
You can scale your apps using
$ kubectl scale deployment <app-name> --replicas <replica-count> -n pizza-store
The default way to update a running app in kubernetes, is to deploy a new image tag to your docker registry and then deploy it using
$ kubectl set image deployment/<app-name>-app <app-name>=<new-image> -n pizza-store
Using livenessProbes and readinessProbe allow you to tell Kubernetes about the state of your applications, in order to ensure availablity of your services. You will need minimum 2 replicas for every application deployment if you want to have zero-downtime deployed. This is because the rolling upgrade strategy first stops a running replica in order to place a new. Running only one replica, will cause a short downtime during upgrades.
my apps doesn't get pulled, because of 'imagePullBackof'
Check the docker registry your Kubernetes cluster is accessing. If you are using a private registry, you should add it to your namespace by kubectl create secret docker-registry (check the docs for more info)
my applications are stopped, before they can boot up
This can occur if your cluster has low resource (e.g. Minikube). Increase the initialDelaySeconds value of livenessProbe of your deployments
my applications are starting very slow, despite I have a cluster with many resources
The default setting are optimized for middle-scale clusters. You are free to increase the JAVA_OPTS environment variable, and resource requests and limits to improve the performance. Be careful!