Fix for Jenkins slowness when Running in AWS EC2 instance | Jenkins Very Slow Upon Starting EC2 Instance after Stopping

Let's say that you have configured Jenkins in AWS EC2 instance and you are using AWS free tier and you are NOT using Elastic IP, so when ever you start EC2 instance after stopping, you would have noticed Jenkins UI is taking a lot of time to come up. You try to access any page in Jenkins, it will be really slow.

What is the root cause of the issue?

Because EC2 configured in AWS free tier account would have new IP after every restart, Jenkins was trying to use old IP address when you are trying to start Jenkins. Due to this issue, Jenkins will be very slow.

Pre-requisites:

• Jenkins is setup in AWS cloud using free-tier account.

There are two ways you can fix this issue:

First option using command line

Make changes in the xml file by logging into EC2 instance through command line using Git bash or any SSH tool.

Connect to Jenkins EC2 instance using Git bash or iTerm:

Navigate to Jenkins installation directory:

cd /var/lib/jenkins/

Modify jenkins.model.JenkinsLocationConfiguration.xml file by executing below command:

sudo nano jenkins.model.JenkinsLocationConfiguration.xml

Make sure you provide Jenkins current URL in below location and restart Jenkins.

sudo service jenkins restart

Now try accessing Jenkins through UI, it will be really performing well.

Second option us using Jenkins UI

Change public URL under Manage Jenkins->System

Change Jenkins URL to current Jenkins URL:

Click on Apply-> Save.

that's it. You will notice Jenkins is performing well now.

Watch steps in YouTube channel: 

Fix for Kubernetes Deployment Error using helm chart | Error: kubernetes cluster unreachable: exec plugin: invalid apiversion "client.authentication.k8s.io/v1alpha1"

 Error: kubernetes cluster unreachable: exec plugin: invalid apiversion "client.authentication.k8s.io/v1alpha1"

 

Root cause and fix:

Downgrading helm version to 3.8.2 would resolve the issue.

curl -L https://git.io/get_helm.sh | bash -s -- --version v3.8.2

No such property: docker for class: groovy.lang.Binding | Jenkins Pipeline Error Docker Build | Jenkins docker pipeline error

 Jenkins Pipeline Error: 

groovy.lang.MissingPropertyException: No such property: docker for class: groovy.lang.Binding.

We most likely encountered the same issue, in order to fix it, install Docker Pipeline plugin in Jenkins:

Root Cause and Fix:

Jenkins need to have Docker Pipeline plug-in to perform Docker builds.

Jenkins > Manage Jenkins > Manage Plugins > Available tab

Search for Docker Pipeline install it, restart Jenkins and you are ready to go.

How to check whether my user data passing to EC2 instance is working | AWS EC2 bootstrap script log

The cloud-init output log file (/var/log/cloud-init-output.log) captures console output so it is easy to debug your scripts following a launch if the instance does not behave the way you intended.

Check the Logs in EC2 instance

Login to EC2 instance, and type the below command:

tail -f /var/log/cloud-init-output.log

This will give the output of bootstrap execution

Certificate verification failed: The certificate is NOT trusted | Jenkins installation Error Fix | Jenkins Installation on Ubuntu 18.0.4

Running sudo apt-get update on my AWS EC2 Ubuntu 18.04.01 LTS instance fails because Certificate verification failed: The certificate is NOT trusted.

Err:6 https://pkg.jenkins.io/debian-stable binary/ Release

Certificate verification failed: The certificate is NOT trusted. The certificate chain uses expired certificate.  Could not handshake: Error in the certificate verification. [IP: 199.232.66.133 443]

Fix for the above error

You need to install certificates to overcome this error:

sudo apt install ca-certificates

sudo apt-get update

Now try installing Jenkins

sudo apt install jenkins -y

stderr: remote: Support for password authentication was removed on August 13, 2021. Please use a personal access token instead | Fix for this issue

 

Support for password authentication was removed on August 13, 2021

How to Fix for the above error:GitHub removed password authentication support from August 13, 2021 instead it recommends to use either OAuth or Personal Access Token.

Create Personal Access Token in GitHub

Go to GitHub.com--> Settings

Go to Developer Settings 

Go to Personal Access tokens --> Generate new token

Enter name for the token, choose no expiration if you don't want your token to expire.

Select repo and click generate token

Now copy the token and use this as password.

Code error 403 when trying to access Kubernetes cluster | Jenkins Kubernetes Deployment Error

When ever you are doing deployment from Jenkins to EKS cluster, you may get this error:

Api call failed with code 403, detailed message: {
  "kind": "Status",
  "apiVersion": "v1",
  "metadata": {
    
  },

"status": "Failure",
  "message": "namespaces is forbidden: User \"system:anonymous\" cannot list namespaces at the cluster scope",
  "reason": "Forbidden",
  "details": {
    "kind": "namespaces"
  },
  "code": 403 

Work around or the fix: 

You get this error because you're getting blocked by RBAC policies. Basically, RBAC policies set to restrict the resources you use and limits a few of your action. 

There are two possibilities, either you haven't created an RBAC or it's somehow restricting the cluster access.

By default, your clusterrolebinding has system:anonymous set which blocks the cluster access.

Execute the following command, it will set a clusterrole as cluster-admin which will give you the required access.

kubectl create clusterrolebinding cluster-system-anonymous --clusterrole=cluster-admin --user=system:anonymous