Kubernetes Jenkins connectivity Issue - jenkins

I set up the kubernetes on EC2 instances over ubuntu platform, everything working fine. But now I have deployed a Jenkins pod, after that, I am able to access the Jenkins in the browser. Now my question is how can I connect Jenkins with my machine.
My Jenkins pod IP:- 10.43.0.8
My Kubernetes Master private IP:- 192.168.105.229
I am able to ping with each other. But how I can access my master machine using Jenkins, so I can create the pods through Jenkins.

There are a few ways to do this. A couple that I can think of:
Use the Jenkins Kubernetes Plugin. If you install this on your Jenkins master (which is also running on a pod) and also if you configure it to talk to the same Kubernetes cluster (meaning the kube-apiserver) then you can create/remove pods using the plugin. More on how to configure authentication and RBAC in Kubernetes
Manually configure Jenkins slaves running as 'user'. Then on the 'user's some directory create a ~/.kube/config that has the configuration to talk to your Kubernetes cluster. From there you can just issue kubectl commands to create/remove pods. You would still need to configure authentication/RBAC.

If you want to access a pod running in Kubernetes you need to expose it as a service and possibly an ingress resource
https://kubernetes.io/docs/concepts/services-networking/service/

Related

Jenkins on k8s and pipeline with docker agent

I want to run my Jenkins behind k8s. We can achieve that with any standard helm chart or our own manifest files. In this case, Jenkins (master only) will run inside a container (Pod).
Now I also want to have a pipeline job that uses docker agent as described here
I am getting confused, about
how and where this docker container will be run (on the same node where Jenkins is running? and suppose the node capacity is over then it needs to run docker agent on a different node)
how does Jenkins will authenticate to run containers on k8s nodes?
I saw the Kubernetes plugin/docker plugin. But those plugins create containers beforehand (or at least we need to set up a template, which decides how containers will start, which image will be used and many more) and connects Jenkins with help of JNLP / ssh. I lose the flexibility to have an image as an agent in that case.
going further, I also like to build custom images on the fly with help of Dockerfile shipped along with code. An example is available in the same link.
I believe this documentation is answering all of your questions: https://devopscube.com/jenkins-build-agents-kubernetes/
With this method, you are not losing your flexibility because your Jenkins master going to create a K8s pod on the fly. Yes, additionally you need JNLP authentication but you can think of that as a sidecar container.
About your first question: If you use exactly that way, your Jenkins jobs going to run under Jenkins master with the same Docker that your Jenkins Master is using.

How to handle "docker-in-docker" problem when using Jenkins inside K8S

New to Kubernetes, a little complex question needs help.
Background
Using Jenkins in GKE (Google Kubernetes Engine)
Want to use jenkins-docker plugin to provide the specific test environment for each type of tests
Don't want to mixin docker binary in the Jenkins image (because it is large)
Don't want docker-in-docker
More specifically, I don't want the Jenkins Pod be a new Docker Server
What I want
Each test environment can create a new pod in GKE Cluster, rather than creating containers inside the Jenkins Pod
P.S.
I have just read some articles, but half of them are telling about "how to use K8S to scale up the Jenkins (using jenkins-slave + jenkins-kubernates plugin)", another half are telling about how to "use docker plugin in a dockerized jenkins container on a bare metal machine (you can use /var/run/docker.sock to communicate between the host and the docker container)", but I cannot find **how to use docker plugin (to provide a specific environment) in a dockerized jenkins container inside K8S

Openshift privileged container access services from openshift namespace

I'm trying to run my custom Jenkins on Openshift. I'm trying to run dockerized pipelines using privileged containers and scc to be able to run docker using my Jenkins. So far, I managed to run the job and it is creating a new Docker container successfully. But, since my new docker is created by Jenkins it doesn't have access to Nexus service on my project. How can I fix this? I was thinking the solution should be for the Jenkins to run docker in the same namespace as my Jenkins.
I'm assuming that you want to run your container in Kubernetes.
On your Deployment I would advise using either a ConfigMap or if you want to keep in encrypted in the cluster you can use a Secret to store your Nexus credentials.
Then you can mount your ConfigMap or Secret under ~/.ivy2/.credentials for example.

How to deploy K8 apps in k8 Cluster through Jenkins?

I tried to use the Kubernetes Continuous Deploy Plugin but its seem it ran on the slave and deploy the app, but I want to deploy K8 Apps in K8 cluster not in jenkins slave.
As it described at wiki-pages you need configure access to your kubernetes cluster.
From documentation:
In the "Kubeconfig" dropdown, select the > kubeconfig stored in Jenkins.
in kubeconfig you store the access to your cluster, without this it would not work.

How do I create a local kubernates cluster in a VM?

I have a set of docker images running in a Kubernates cluster on GKE. I have a Jenkins server running on a VM in GKE.
I have docker builds and GKE deploys running on the Jenkins server, but I would like to start up a 'local' cluster on the Jenkins server after successful builds, run my dockers in that cluster, run my tests towards the cluster, and then close down the local cluster before deploying the docker images to GKE.
I know about minikube, but they state that you are not able to run nested VM's, and I wonder if this blocks my dream of test my cluster before deploying it?
Do I have to run my local cluster on a physical server to be able to run my tests, or is there a solution to my problem?
Have you considered using kubeadm?
You can run a Kubernetes cluster within your Jenkins VM. Setup is a bit different than minikube and it's still in beta but it will let you test your cluster before the final deployment.

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