Cloud agent provisioning (EC2, Azure) in Jenkins - Step-by-Step Execution

Process Flow - Cloud agent provisioning (EC2, Azure)

Start Jenkins Job

↓

Select Cloud Provider

↓

Provision EC2

↓

Configure Agent

↓

Agent Ready for Job Execution

↓

Run Job

↓

Cleanup

↓

End

This flow shows Jenkins starting a job, choosing a cloud provider (EC2 or Azure), provisioning the agent, configuring it, running the job, and cleaning up.

Execution Sample

Jenkins

pipeline {
  agent {
    label 'ec2-agent'
  }
  stages {
    stage('Build') {
      steps {
        echo 'Building on EC2 agent'
      }
    }
  }
}

This Jenkins pipeline provisions an EC2 cloud agent labeled 'ec2-agent' and runs a build stage on it.

Process Table

Step	Action	Evaluation	Result
1	Start Jenkins job	Job triggered	Job starts execution
2	Select cloud provider	Provider = AWS EC2	EC2 provisioning begins
3	Provision EC2 instance	Request EC2 instance with label 'ec2-agent'	EC2 instance launched and connected
4	Configure agent	Install Jenkins agent on EC2	Agent ready and connected to Jenkins master
5	Run build stage	Execute echo command	Output: 'Building on EC2 agent'
6	Job completes	Build stage finished	Job ends successfully
7	Cleanup	Terminate EC2 instance	EC2 instance terminated
8	Exit	No more stages	Job fully completed

💡 Job ends after build stage completes and EC2 instance is terminated.

Status Tracker

Variable	Start	After Step 3	After Step 4	After Step 7	Final
cloud_provider	null	AWS EC2	AWS EC2	AWS EC2	null
agent_status	not provisioned	provisioning	ready	terminating	terminated
job_status	not started	running	running	completed	completed

Key Moments - 2 Insights

Why does the agent_status change from 'provisioning' to 'ready' after step 4?

Because after the EC2 instance is launched (step 3), Jenkins installs and connects the agent software on it (step 4), making the agent ready to run jobs as shown in execution_table row 4.

Why is the EC2 instance terminated after the job completes?

To save costs and resources, Jenkins cleans up by terminating the EC2 instance after the job finishes, as shown in execution_table step 7.

Visual Quiz - 3 Questions

Look at the execution table, what is the agent_status after step 4?

A provisioning

B ready

C terminated

D not provisioned

💡 Hint

Check the variable_tracker table under 'agent_status' after Step 4.

At which step does the EC2 instance get terminated?

A Step 7

B Step 6

C Step 5

D Step 8

💡 Hint

Look at the execution_table row describing cleanup and termination.

If the cloud_provider was changed to Azure, which step would change in the execution table?

A Step 4

B Step 3

C Step 2

D Step 5

💡 Hint

Step 2 is where the cloud provider is selected.

Concept Snapshot

Jenkins Cloud Agent Provisioning:
- Define cloud provider in pipeline (e.g., AWS EC2 or Azure VM).
- Jenkins requests and launches cloud VM as agent.
- Agent installs Jenkins software and connects.
- Job runs on this dynamic agent.
- After job, agent VM is terminated to save cost.

Full Transcript

This visual execution shows how Jenkins provisions cloud agents on EC2 or Azure. The job starts, selects a cloud provider, provisions the VM, configures the Jenkins agent, runs the job, and then cleans up by terminating the VM. Variables like agent_status and job_status change step-by-step. Key moments include understanding when the agent becomes ready and why cleanup happens. The quiz tests knowledge of these steps and variable states.