Artifact retention policies in Jenkins - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an artifact in Jenkins?

An artifact is a file or set of files produced by a Jenkins build, such as compiled code, reports, or logs, that can be saved and used later.

beginner

Why do we need artifact retention policies in Jenkins?

To control how long build artifacts are kept, saving storage space and keeping Jenkins clean by deleting old or unnecessary files automatically.

intermediate

How can you configure artifact retention in a Jenkins job?

By setting 'Discard old builds' in the job configuration and specifying how many builds or days to keep artifacts and builds.

beginner

What happens if you do not set an artifact retention policy?

Artifacts and builds will be kept forever, which can use a lot of disk space and slow down Jenkins over time.

intermediate

Can artifact retention policies be automated in Jenkins pipelines?

Yes, using pipeline scripts you can add steps to delete old artifacts or limit how many builds keep artifacts automatically.

What is the main purpose of artifact retention policies in Jenkins?

A To backup artifacts to cloud storage

B To speed up the build process

C To increase the number of builds stored

D To save disk space by deleting old build artifacts

Artifact retention policies help manage disk space by removing old or unnecessary build artifacts.

Where do you configure artifact retention settings in a Jenkins freestyle job?

A In the 'Discard old builds' section of the job configuration

B In the Jenkins global settings

C In the build triggers section

D In the post-build actions

The 'Discard old builds' section allows you to set how many builds and artifacts to keep.

What is a risk of not setting artifact retention policies?

A Jenkins will delete all builds automatically

B Artifacts will be uploaded to the wrong location

C Disk space may fill up causing Jenkins to slow down or fail

D Builds will not run

Without retention policies, artifacts accumulate and can fill disk space, impacting Jenkins performance.

Can artifact retention be controlled in Jenkins pipelines?

A No, only freestyle jobs support retention policies

B Yes, using pipeline scripts to delete or limit artifacts

C Only by installing plugins

D Only through Jenkins global configuration

Pipeline scripts can include steps to manage artifact retention automatically.

Which of these is NOT a typical retention policy setting in Jenkins?

A Maximum artifact file size

B Number of days to keep builds

C Number of builds to keep

D Delete artifacts older than a certain date

Jenkins retention policies do not usually limit artifact file size, but focus on build count or age.

Explain how artifact retention policies help maintain Jenkins performance and storage.

Think about what happens if old files are never deleted.

Describe the steps to set up artifact retention in a Jenkins freestyle job.

Look for the section that controls old build cleanup.

Practice

1. What is the main purpose of artifact retention policies in Jenkins?

easy

A. To manage disk space by deleting old build files

B. To speed up the build process by caching dependencies

C. To increase the number of builds stored indefinitely

D. To automatically trigger builds on code changes

Solution

1. Step 1: Understand artifact retention policies

   Artifact retention policies control how long build files are kept to avoid using too much disk space.

2. Step 2: Identify the main goal

   The main goal is to delete old build files to free up disk space.

3. Final Answer:

   To manage disk space by deleting old build files -> Option A

4. Quick Check:

   Artifact retention = disk space management [OK]

Hint: Retention policies delete old builds to save space [OK]

Common Mistakes:

• Confusing retention with build triggering
• Thinking retention speeds up builds
• Assuming retention keeps all builds forever

2. Which Jenkins pipeline syntax correctly sets a retention policy to keep only the last 5 builds?

easy

A. archiveArtifacts(numToKeepStr: '5')

B. buildDiscarder(keepLast: 5)

C. buildDiscarder(logRotator(numToKeepStr: '5'))

D. archiveArtifacts(logRotator(numToKeepStr: '5'))

Solution

1. Step 1: Identify correct syntax for retention

   Retention uses buildDiscarder with logRotator to specify how many builds to keep.

2. Step 2: Check option correctness

   buildDiscarder(logRotator(numToKeepStr: '5')) uses correct syntax: buildDiscarder(logRotator(numToKeepStr: '5')). Others misuse archiveArtifacts or wrong parameters.

3. Final Answer:

   buildDiscarder(logRotator(numToKeepStr: '5')) -> Option C

4. Quick Check:

   Retention uses buildDiscarder + logRotator [OK]

Hint: Retention = buildDiscarder with logRotator [OK]

Common Mistakes:

• Using archiveArtifacts to set retention
• Wrong parameter names like keepLast
• Nesting logRotator inside archiveArtifacts

3. Given this Jenkins pipeline snippet:

pipeline {
  options {
    buildDiscarder(logRotator(numToKeepStr: '3', daysToKeepStr: '7'))
  }
  stages {
    stage('Build') {
      steps {
        echo 'Building...'
      }
    }
  }
}

What happens to builds older than 7 days or beyond the last 3 builds?

medium

A. They are deleted to free disk space

B. They are archived permanently

C. They trigger a new build automatically

D. They are kept indefinitely

Solution

1. Step 1: Understand logRotator parameters

   It keeps only the last 3 builds and deletes builds older than 7 days.

2. Step 2: Determine effect on old builds

   Builds older than 7 days or beyond the last 3 are deleted to save space.

3. Final Answer:

   They are deleted to free disk space -> Option A

4. Quick Check:

   logRotator deletes old builds [OK]

Hint: logRotator deletes builds older than days or count [OK]

Common Mistakes:

• Thinking builds are archived permanently
• Assuming builds trigger new builds
• Believing builds are kept forever

4. You wrote this Jenkins pipeline snippet to keep artifacts for 10 days:

options {
  buildDiscarder(logRotator(artifactDaysToKeep: '10'))
}

But artifacts are not deleted after 10 days. What is the likely problem?

medium

A. logRotator does not support artifact retention

B. The buildDiscarder option must be inside stages

C. You must use archiveArtifacts to delete old artifacts

D. The parameter name should be artifactDaysToKeepStr, not artifactDaysToKeep

Solution

1. Step 1: Check logRotator parameter names

   logRotator parameters for strings end with 'Str', like artifactDaysToKeepStr.

2. Step 2: Identify the syntax issue

   Missing 'Str' means the parameter is not recognized, so default retention applies and artifacts aren't deleted after 10 days.

3. Final Answer:

   The parameter name should be artifactDaysToKeepStr, not artifactDaysToKeep -> Option D

4. Quick Check:

   logRotator params end with 'Str' [OK]

Hint: logRotator params like artifactDaysToKeepStr end with Str [OK]

Common Mistakes:

• Using wrong parameter names
• Expecting logRotator to delete artifacts
• Placing buildDiscarder outside options block

5. You want to keep artifacts only for the last 4 builds and delete older artifacts automatically, while keeping older builds. Which Jenkins pipeline snippet correctly applies this retention policy?

hard

A. steps { archiveArtifacts artifacts: '**/*', onlyIfSuccessful: true, retentionDays: 4 }

B. options { buildDiscarder(logRotator(artifactNumToKeepStr: '4')) }

C. options { buildDiscarder(logRotator(numToKeepStr: '4')) } steps { archiveArtifacts artifacts: '**/*', onlyIfSuccessful: true }

D. steps { archiveArtifacts artifacts: '**/*', keepOnlyLast: 4 }

Solution

1. Step 1: Understand roles for artifact-specific retention

   To keep artifacts from only the last 4 builds while retaining builds, use artifactNumToKeepStr.

2. Step 2: Check option correctness

   options { buildDiscarder(logRotator(artifactNumToKeepStr: '4')) }: buildDiscarder(logRotator(artifactNumToKeepStr: '4')) keeps artifacts from last 4 builds, deletes older artifacts, keeps all builds. C deletes old builds too. B/D use invalid params.

3. Final Answer:

   options { buildDiscarder(logRotator(artifactNumToKeepStr: '4')) } -> Option B

4. Quick Check:

   artifactNumToKeepStr for artifacts only [OK]

Hint: artifactNumToKeepStr keeps artifacts from last N builds [OK]

Common Mistakes:

• Using invalid parameters like retentionDays or keepOnlyLast
• Trying to control retention only via archiveArtifacts
• Misplacing buildDiscarder outside options block