Disk space management in Jenkins - Commands & Configuration

Introduction

Disk space management in Jenkins helps keep the server clean and running smoothly by removing old build files and logs that take up too much space.

When Jenkins server disk is filling up and builds start failing due to lack of space

When you want to automatically delete old build artifacts to save storage

When you want to keep only recent build logs for troubleshooting and remove older ones

When you want to prevent Jenkins from slowing down because of too many stored files

When you want to schedule cleanup tasks to run regularly without manual intervention

Config File - Jenkinsfile

Jenkinsfile

pipeline {
    agent any
    options {
        buildDiscarder(logRotator(numToKeepStr: '10', artifactNumToKeepStr: '5'))
    }
    stages {
        stage('Build') {
            steps {
                echo 'Building the project'
            }
        }
    }
}

This Jenkinsfile defines a pipeline with a buildDiscarder option that automatically deletes old builds and artifacts.

numToKeepStr: '10' means keep only the last 10 builds.

artifactNumToKeepStr: '5' means keep artifacts only for the last 5 builds.

This helps manage disk space by cleaning up old data.

Commands

This command lists all Jenkins jobs on the server to identify which jobs exist before applying disk space management.

Terminal

java -jar jenkins-cli.jar -s http://localhost:8080 list-jobs

Expected Output

example-job

build-app

test-pipeline

This command downloads the configuration XML of the 'example-job' to edit disk space settings if needed.

Terminal

java -jar jenkins-cli.jar -s http://localhost:8080 get-job example-job > example-job.xml

Expected Output

<?xml version='1.0' encoding='UTF-8'?>

<project>

  <actions/>

  <description>Example job</description>

  <keepDependencies>false</keepDependencies>

  <properties/>

  <scm class="hudson.scm.NullSCM"/>

  <canRoam>true</canRoam>

  <disabled>false</disabled>

  <blockBuildWhenDownstreamBuilding>false</blockBuildWhenDownstreamBuilding>

  <blockBuildWhenUpstreamBuilding>false</blockBuildWhenUpstreamBuilding>

  <triggers/>

  <concurrentBuild>false</concurrentBuild>

  <builders/>

  <publishers/>

  <buildWrappers/>

</project>

This command uploads the edited job configuration XML back to Jenkins to apply disk space management settings.

Terminal

java -jar jenkins-cli.jar -s http://localhost:8080 update-job example-job < example-job.xml

Expected Output

No output (command runs silently)

This command lists builds of the 'example-job' to verify which builds exist before and after cleanup.

Terminal

java -jar jenkins-cli.jar -s http://localhost:8080 list-builds example-job

Expected Output

#1

#2

#3

#4

#5

#6

#7

#8

#9

#10

#11

#12

Key Concept

If you remember nothing else, remember: Jenkins can automatically delete old builds and artifacts to save disk space using build discarders.

Common Mistakes

Not setting build discarders in the Jenkinsfile or job configuration

Old builds and artifacts accumulate, filling disk space and causing Jenkins to slow down or fail builds.

Always configure build discarders with limits on how many builds and artifacts to keep.

Setting very high numbers for builds to keep, like 1000

This defeats the purpose of cleanup and still uses too much disk space.

Choose reasonable limits based on your storage capacity and project needs, like keeping only the last 10 builds.

Manually deleting build folders from Jenkins home directory

This can corrupt Jenkins metadata and cause errors.

Use Jenkins UI or configuration options to safely discard old builds.

Summary

Use the buildDiscarder option in Jenkinsfile to automatically clean old builds and artifacts.

Use Jenkins CLI commands to list jobs, get and update job configurations for disk space management.

Verify build cleanup by listing builds before and after applying discarders.