kubernetes-up-and-running/examples

Example code and files from "Kubernetes: Up and Running"

examples's Issues

Error to setup sentinnel and replicate data between nodes

Hello,

Pods are setup on my GCP cluster but sentinel returns an error and replication between nodes is not ok.

If I try to determine which server the Redis sentinel believes is the master, I get the following :
$ kubectl exec redis-2 -c redis -- redis-cli -p 26379 sentinel get-master-addr-by-name redis
Could not connect to Redis at 127.0.0.1:26379: Connection refused

If I check sentinel logs
$ kubectl logs statefulsets/redis sentinel
Waiting for server
ping: bad address 'redis-0.redis'

And if I set foo 10 on redis-0 I don't get key on redis-2

Why I get bad address ?
What can I do ?
Thank you

Examples of lessons 2-4

Why does examples start from chapter when examples are available starting from chapter 2 in the book? And why are examples separate from guard repository anyway? The book has a chaotic structure and so the examples. It takes a while to get an overview and what to do first.

Error: unknown flag: --from-file

Hey! When I run this command from the book for example 14-3:

kubectl apply cm --from-file ghost-config.js ghost-config

I get this error:

Error: unknown flag: --from-file

I'm on kubectl version:

Client Version: version.Info{Major:"1", Minor:"8", GitVersion:"v1.8.3", GitCommit:"f0efb3cb883751c5ffdbe6d515f3cb4fbe7b7acd", GitTreeState:"clean", BuildDate:"2017-11-08T18:39:33Z", GoVersion:"go1.8.3", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.4", GitCommit:"d6f433224538d4f9ca2f7ae19b252e6fcb66a3ae", GitTreeState:"dirty", BuildDate:"2017-06-22T04:31:09Z", GoVersion:"go1.7.5", Compiler:"gc", Platform:"linux/amd64"}

Do I need to be on an older version for that invocation to work?

For anyone else with this problem, I used this command to get it working:

kubectl create configmap ghost-config --from-file ghost-config.js

Example 8-1-kuard-rs.yaml does not work

Trying to run the example 8-1-kuard-rs.yaml with kubectl v1.16.3 and minikube v.1.6.2 and getting validation error:

➜ kubernetes-up-and-running_examples git:(master) ✗ kubectl apply -f 8-1-kuard-rs.yaml
error: error validating "8-1-kuard-rs.yaml": error validating data: ValidationError(ReplicaSet.spec): missing required field "selector" in io.k8s.api.apps.v1.ReplicaSetSpec; if you choose to ignore these errors, turn validation off with --validate=false
➜ kubernetes-up-and-running_examples git:(master) ✗ kubectl apply -f 8-1-kuard-rs.yaml
The ReplicaSet "kuard" is invalid: spec.template.metadata.labels: Invalid value: map[string]string{"app":"kuard", "version":"2"}: `selector` does not match template `labels`
➜ kubernetes-up-and-running_examples git:(master) ✗ kubectl version
Client Version: version.Info{Major:"1", Minor:"16", GitVersion:"v1.16.3", GitCommit:"b3cbbae08ec52a7fc73d334838e18d17e8512749", GitTreeState:"clean", BuildDate:"2019-11-13T11:23:11Z", GoVersion:"go1.12.12", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"17", GitVersion:"v1.17.0", GitCommit:"70132b0f130acc0bed193d9ba59dd186f0e634cf", GitTreeState:"clean", BuildDate:"2019-12-07T21:12:17Z", GoVersion:"go1.13.4", Compiler:"gc", Platform:"linux/amd64"}
➜ kubernetes-up-and-running_examples git:(master) ✗ minikube version
minikube version: v1.6.2
commit: 54f28ac5d3a815d1196cd5d57d707439ee4bb392

13-2yaml can not work

kubectl create -f 13-2.yaml
13-2 yaml is writed as

kind: Service
apiVersion: v1
metadata:
name: external-ip-database
I get the error

The Service "external-ip-database" is invalid: spec.ports: Required value

5-1 yaml gives error

When trying to deploy the 5-1 example yaml:
$ kubectl apply -f kuard-pod.yaml
error: error validating "kuard-pod.yaml": error validating data: ValidationError(Pod.metadata): unknown field "spec" in io.k8s.apimachinery.pkg.apis.meta.v1.ObjectMeta; if you choose to ignore these errors, turn validation off with --validate=false

$ kubectl version
Client Version: version.Info{Major:"1", Minor:"9", GitVersion:"v1.9.0", GitCommit:"925c127ec6b946659ad0fd596fa959be43f0cc05", GitTreeState:"clean", BuildDate:"2017-12-15T21:07:38Z", GoVersion:"go1.9.2", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"8", GitVersion:"v1.8.0", GitCommit:"0b9efaeb34a2fc51ff8e4d34ad9bc6375459c4a4", GitTreeState:"clean", BuildDate:"2017-11-29T22:43:34Z", GoVersion:"go1.9.1", Compiler:"gc", Platform:"linux/amd64"}

Update: Example 5-2 worked ok.
Also updated error message to correct one

-jjd

I have book 3rd edition will these examples work? they say last update 5 years ago

hi guys

I have book 3rd edition will these examples work? they say last update 5 years ago

of there is a more recent repo?

thanks

14-10-redis.yaml error : Error from server (BadRequest): a container name must be specified for pod redis-0, choose one of: [redis sentinel]

Hello,

Thank you for the book, great help.
I try to use the Redis configuration on my prod on GCP but following the steps, I get the following error :

Error from server (BadRequest): a container name must be specified for pod redis-0, choose one of: [redis sentinel]

My configuration is the same present in the book
https://github.com/kubernetes-up-and-running/examples/blob/master/14-10-redis.yaml

apiVersion: apps/v1beta1
kind: StatefulSet
metadata:
name: redis
spec:
replicas: 3
serviceName: redis
template:
metadata:
labels:
app: redis
spec:
containers:
- command: [sh, -c, source /redis-config/init.sh ]
image: redis:3.2.7-alpine
name: redis
ports:
- containerPort: 6379
name: redis
volumeMounts:
- mountPath: /redis-config
name: config
- mountPath: /redis-data
name: data
- command: [sh, -c, source /redis-config/sentinel.sh]
image: redis:3.2.7-alpine
name: sentinel
volumeMounts:
- mountPath: /redis-config
name: config
volumes:
- configMap:
defaultMode: 420
name: redis-config
name: config
- emptyDir:
name: data

For example :
po/redis-0 1/2 CrashLoopBackOff 4 2m
po/redis-1 1/2 CrashLoopBackOff 4 2m

Same error :
$ kubectl logs po/redis-1 -p
Error from server (BadRequest): a container name must be specified for pod redis-1, choose one of: [redis sentinel]

Thank you for your help,

Julien

Example 5-1-kuard-pod.yaml error

When I run
kubectl apply -f examples/5-1-kuard-pod.yaml
I get this error:
error: error validating "examples/5-1-kuard-pod.yaml": error validating data: found invalid field spec for v1.ObjectMeta; if you choose to ignore these errors, turn validation off with --validate=false
And when I add --validate=false and run:
kubectl apply -f examples/5-1-kuard-pod.yaml --validate=false
I get this error:
The Pod "kuard" is invalid: spec.containers: Required value
I am running K8S on Azure.

5-2. kuard-pod-health.yaml does not work

I have the following conf saved in kuard-prod-health.yaml

apiVersion: v1
kind: Pod
metadata:
  name: kuard
spec:
  containers:
    - image: gcr.io/kuar-demo/kuard-amd64:1
      name: kuard
      livenessProbe:
        httpGet:
          path: /healthy
          port: 8080
        initialDelaySeconds: 5
        timeoutSeconds: 1
        periodSeconds: 10
        failureThreshold: 3
      ports:
        - containerPort: 8080
          name: http
          protocol: TCP

However when I try to apply the conf:
kubectl apply -f kuard-prod-health.yaml

I get this error:

The Pod "kuard" is invalid: spec: Forbidden: pod updates may not change fields other than spec.containers[*].image, spec.initContainers[*].image, spec.activeDeadlineSeconds or spec.tolerations (only additions to existing tolerations)

--replicas flag has been deprecated

Commands in chapter 8 rely on the depreciated replicas. This is several places throughout the book.

It was removed in 1.18.

https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.18.md#deprecation-4

kubectl run be-default \

--image=gcr.io/kuar-demo/kuard-amd64:blue
--replicas=3
--port=8080
Flag --replicas has been deprecated, has no effect and will be removed in the future.
pod/be-default created

Default health settings for kuard-pod-health.yaml does not work

Originally the Healthrequests are instructed to go to:

httpGet:
path: /healthy
port: 8080

While the failures are generated on http://localhost:8080/ready and http://localhost:8080/healthy would always return http 200. No restart will be happening.
yaml file should be changed to

httpGet:
path: /ready
port: 8080