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Questions tagged [kubernetes]

KUBERNETES QUESTIONS MUST BE SPECIFICALLY RELATED TO SOFTWARE DEVELOPMENT. Configuration and deployment is off-topic here. A good rule of thumb is, if it happens outside the pod, it's probably off-topic. If it's about code running inside the pod, it's probably OK.

Kubernetes is a system for managing containerized applications across multiple hosts, providing basic mechanisms for deployment, maintenance, and scaling of applications. Its APIs are intended to serve as the foundation for an open ecosystem of tools, automation systems, and higher-level API layers. Kubernetes can run on various cloud providers, on premises in VMs, or on bare metal machines.

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57333 questions
218
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20 answers

Sharing secret across namespaces

Is there a way to share secrets across namespaces in Kubernetes? My use case is: I have the same private registry for all my namespaces and I want to avoid creating the same secret for each.
matth3o
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Multiple environments (Staging, QA, production, etc) with Kubernetes

What is considered a good practice with K8S for managing multiple environments (QA, Staging, Production, Dev, etc)? As an example, say that a team is working on a product which requires deploying a few APIs, along with a front-end application.…
Yoanis Gil
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21 answers

My kubernetes pods keep crashing with "CrashLoopBackOff" but I can't find any log

This is what I keep getting: [root@centos-master ~]# kubectl get pods NAME READY STATUS RESTARTS AGE nfs-server-h6nw8 1/1 Running 0 1h nfs-web-07rxz 0/1 CrashLoopBackOff 8 …
Lucifer
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6 answers

How kubectl port-forward works?

kubectl exposes commands that can be used to create a Service for an application and assigns an IP address to access it from internet. As far as I understand, to access any application within Kubernetes cluster there should be a Service resource…
karthikeayan
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210
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10 answers

How to set multiple commands in one yaml file with Kubernetes?

In this official document, it can run command in a yaml config file: https://kubernetes.io/docs/tasks/configure-pod-container/ apiVersion: v1 kind: Pod metadata: name: hello-world spec: # specification of the pod’s contents restartPolicy:…
scho
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6 answers

What's the best way to share/mount one file into a pod?

I was considering using secrets to mount a single file but it seems that you can only mount directory that will overwrites all the other content. How can I share a single config file without mounting a directory?
Smana
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204
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8 answers

How to delete all resources from Kubernetes one time?

Include: Daemon Sets Deployments Jobs Pods Replica Sets Replication Controllers Stateful Sets Services ... If has replicationcontroller, when delete some deployments they will regenerate. Is there a way to make kubenetes back to initialize status?
online
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15 answers

Restart container within pod

I have a pod test-1495806908-xn5jn with 2 containers. I'd like to restart one of them called container-test. Is it possible to restart a single container within a pod and how? If not, how do I restart the pod? The pod was created using a…
s5s
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199
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7 answers

Kubernetes Deployments vs StatefulSets

I've been doing a lot of digging on Kubernetes, and I'm liking what I see a lot! One thing I've been unable to get a clear idea about is what the exact distinctions are between the Deployment and StatefulSet resources and in which scenarios would…
SS781
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3 answers

What is a headless service, what does it do/accomplish, and what are some legitimate use cases for it?

I've read a couple of passages from some books written on Kubernetes as well as the page on headless services in the docs. But I'm still unsure what it really actually does and why someone would use it. Does anyone have a good understanding of it,…
John Lexus
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19 answers

Checking Kubernetes pod CPU and memory utilization

I am trying to see how much memory and CPU is utilized by a kubernetes pod. I ran the following command for this: kubectl top pod podname --namespace=default I am getting the following error: W0205 15:14:47.248366 2767 top_pod.go:190] Metrics…
aniztar
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190
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14 answers

How to sign in kubernetes dashboard?

I just upgraded kubeadm and kubelet to v1.8.0. And install the dashboard following the official document. $ kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml After that,…
ichbinblau
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177
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19 answers

Decoding Kubernetes secret

I inherited a Kubernetes/Docker setup, and I accidentally crashed the pod by changing something relating to the DB password. I am trying to troubleshoot this. I don't have much Kubernetes or Docker experience, so I'm still learning how to do…
Steven Matthews
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9 answers

How can I update a secret on Kubernetes when it is generated from a file?

I've created a secret using kubectl create secret generic production-tls \ --from-file=./tls.key \ --from-file=./tls.crt If I'd like to update the values - how can I do this?
Chris Stryczynski
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15 answers

How do you cleanly list all the containers in a kubernetes pod?

I am looking to list all the containers in a pod in a script that gather's logs after running a test. kubectl describe pods -l k8s-app=kube-dns returns a lot of info, but I am just looking for a return like: etcd kube2sky skydns I don't see a…
Charles L.
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