ec2-spot-jenkins-plugin

Use jenkinsci/ec2-fleet-plugin instead of awslabs/ec2-spot-jenkins-plugin

The EC2 Spot Jenkins plugin launches EC2 Spot instances as worker nodes for Jenkins CI server, automatically scaling the capacity with the load.

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Overview
Change Log
Usage
Development

Overview

This plugin uses Spot Fleet to launch instances instead of directly launching them by itself. Amazon EC2 attempts to maintain your Spot fleet's target capacity as Spot prices change to maintain the fleet within the specified price range. For more information, see How Spot Fleet Works.

Change Log

This plugin is using SemVersion which means that each plugin version looks like

<major>.<minor>.<bugfix>

major = increase only if non back compatible changes
minor = increase when new features
bugfix = increase when bug fixes

As result you safe to update plugin to any version until first number is the same with what you have.

https://github.com/jenkinsci/ec2-fleet-plugin/releases

Usage

Setup

1. Get AWS Account

AWS account

2. Create IAM User

Specify programmatic access during creation, and record credentials which will be used by Jenkins EC2 Fleet Plugin to connect to your Spot Fleet

3. Configure User permissions

Add inline policy to the user to allow it use EC2 Spot Fleet AWS documentation about that

  {
      "Version": "2012-10-17",
      "Statement": [
          {
              "Effect": "Allow",
              "Action": [
                  "ec2:*"
              ],
              "Resource": "*"
          },
          {
              "Effect": "Allow",
              "Action": [
                "iam:ListRoles",
                "iam:PassRole",
                "iam:ListInstanceProfiles"
              ],
              "Resource": "*"
          }
      ]
  }

4. Create EC2 Spot Fleet

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/spot-fleet-requests.html#create-spot-fleet

Make sure that you:

Checked Maintain target capacity why
specify an SSH key that will be used later by Jenkins.

5. Configure Jenkins

Once the fleet is launched, you can set it up by adding a new EC2 Fleet cloud in the Jenkins

Goto Manage Jenkins > Plugin Manager
Install EC2 Fleet Jenkins Plugin
Goto Manage Jenkins > Configure System
Click Add a new cloud and select Amazon SpotFleet
Configure credentials and specify EC2 Spot Fleet which you want to use

Scaling

You can specify the scaling limits in your cloud settings. By default, Jenkins will try to scale fleet up if there are enough tasks waiting in the build queue and scale down idle nodes after a specified idleness period.

You can use the History tab in the AWS console to view the scaling history.

Groovy

Below Groovy script to setup EC2 Spot Fleet Plugin for Jenkins and configure it, you can run it by Jenkins Script Console

import com.amazonaws.services.ec2.model.InstanceType
import com.cloudbees.jenkins.plugins.sshcredentials.impl.BasicSSHUserPrivateKey.DirectEntryPrivateKeySource
import com.cloudbees.jenkins.plugins.sshcredentials.impl.BasicSSHUserPrivateKey
import com.cloudbees.jenkins.plugins.awscredentials.AWSCredentialsImpl
import hudson.plugins.sshslaves.SSHConnector
import hudson.plugins.sshslaves.verifiers.NonVerifyingKeyVerificationStrategy
import com.cloudbees.plugins.credentials.*
import com.cloudbees.plugins.credentials.domains.Domain
import hudson.model.*
import com.amazon.jenkins.ec2fleet.EC2FleetCloud
import jenkins.model.Jenkins

// just modify this config other code just logic
config = [
    region: "us-east-1",
    fleetId: "...",
    idleMinutes: 10,
    minSize: 0,
    maxSize: 10,
    numExecutors: 1,
    awsKeyId: "...",
    secretKey: "...",
    ec2PrivateKey: '''-----BEGIN RSA PRIVATE KEY-----
...
-----END RSA PRIVATE KEY-----'''
]

// https://github.com/jenkinsci/aws-credentials-plugin/blob/aws-credentials-1.23/src/main/java/com/cloudbees/jenkins/plugins/awscredentials/AWSCredentialsImpl.java
AWSCredentialsImpl awsCredentials = new AWSCredentialsImpl(
  CredentialsScope.GLOBAL,
  "aws-credentials",
  config.awsKeyId,
  config.secretKey,
  "my aws credentials"
)
 
BasicSSHUserPrivateKey instanceCredentials = new BasicSSHUserPrivateKey(
  CredentialsScope.GLOBAL,
  "instance-ssh-key",
  "ec2-user",
  new DirectEntryPrivateKeySource(config.ec2PrivateKey),
  "", 
  "my private key to ssh ec2 for jenkins"
)
 
// find detailed information about parameters on plugin config page or
// https://github.com/jenkinsci/ec2-fleet-plugin/blob/master/src/main/java/com/amazon/jenkins/ec2fleet/EC2FleetCloud.java
EC2FleetCloud ec2FleetCloud = new EC2FleetCloud(
  "", // fleetCloudName 
  awsCredentials.id,
  "",
  config.region,
  config.fleetId,
  "ec2-fleet",  // labels
  "", // fs root
  new SSHConnector(22, 
                   instanceCredentials.id, "", "", "", "", null, 0, 0, 
                   // consult doc for line below, this one say no host verification, but you can use more strict mode
                   // https://github.com/jenkinsci/ssh-slaves-plugin/blob/master/src/main/java/hudson/plugins/sshslaves/verifiers/NonVerifyingKeyVerificationStrategy.java
                   new NonVerifyingKeyVerificationStrategy()),
  false, // if need to use privateIpUsed
  false, // if need alwaysReconnect
  config.idleMinutes, // if need to allow downscale set > 0 in min
  config.minSize, // minSize
  config.maxSize, // maxSize
  config.numExecutors, // numExecutors
  false, // addNodeOnlyIfRunning
  false, // restrictUsage allow execute only jobs with proper label
)
 
// get Jenkins instance
Jenkins jenkins = Jenkins.getInstance()
// get credentials domain
def domain = Domain.global()
// get credentials store
def store = jenkins.getExtensionList('com.cloudbees.plugins.credentials.SystemCredentialsProvider')[0].getStore()
// add credential to store
store.addCredentials(domain, awsCredentials)
store.addCredentials(domain, instanceCredentials)
// add cloud configuration to Jenkins
jenkins.clouds.add(ec2FleetCloud)
// save current Jenkins state to disk
jenkins.save()

Preconfigure Slave

Sometimes you need to prepare slave (which is EC2 instance) before Jenkins could use it. For example install some software which will be required by your builds like Maven etc.

For those cases you have a few options, described below:

Amazon EC2 AMI

Greate for static preconfiguration

AMI allows you to create custom images for your EC2 instances. For example you can create image with Linux plus Java, Maven etc. as result when EC2 fleet will launch new EC2 instance with this AMI it will automatically get all required software. Nice =)

Create custom AMI as described here
Create EC2 Spot Fleet with this AMI

EC2 instance User Data

EC2 instance allows to specify special script User Data which will be executed when EC2 instance is created. That's allow you to do some customization for particular instance.

However, EC2 instance doesn't provide any information about User Data execution status, as result Jenkins could start task on new instances while User Data still in progress.

To avoid that you can use Jenkins SSH Launcher Prefix Start Agent Command setting to specify command which should fail if User Data is not finished, in that way Jenkins will not be able to connect to instance until User Data is not done more

Prepare User Data script
Open Jenkins
Goto Manage Jenkins > Configure Jenkins
Find proper fleet configuration and click Advance for SSH Launcher
Add checking command into field Prefix Start Slave Command
- example java -version &&
To apply for existent instances restart Jenkins or Delete Nodes from Jenkins so they will be reconnected

Development

Plugin usage statistic per Jenkins version here

Releasing

https://jenkins.io/doc/developer/publishing/releasing/

mvn release:prepare release:perform

Jenkins 2 can't connect by SSH

https://issues.jenkins-ci.org/browse/JENKINS-53954

Install Java 8 on EC2 instance

sudo yum install java-1.8.0
sudo yum remove java-1.7.0-openjdk
java -version