How to discard Jenkins old builds from project or Pipeline?

When we work with Jenkins, we surely run our project(s) multiple times and this will result in a long queue of the build History list that mostly is of no use after certain numbers.

How to discard Jenkins old builds from project or Pipeline?

1) If you have access to the "Manage Jenkins" section of your Jenkins then you can run the below-mentioned script to clean your project Build History.
Note* This will reset the build number to 1 on your next run.

a) Access your Jenkins HP > Manage Jenkins > Script Console

b) Copy-Paste this script to your Console Script text area and update the "myproject_name" with your project name where you need to clean the build history and hit the "Run button".


def yourJobName = "myproject_name"
def job = Jenkins.instance.getItem(yourJobName)
job.getBuilds().each { it.delete() }
job.nextBuildNumber = 1
job.save()

This should clean your Build History for that particular project but if you're using the multi-branch pipeline, then you need to make the following changes in the above script:

def yourJobName = "path to your pipeline-'folder_name_job_name'"
def job = Jenkins.getInstance().getItemByFullName(yourJobName, Job.class)

Note* At times, if you still see your old builds on UI then after removing builds from the file system using above mentioned script you need to go to Manage Jenkins in the Jenkins GUI and click Reload Configuration from Disk.

2) If you don't have access to the "Manage Jenkins" section of your Jenkins, there is another way to remove old builds i.e. using a "discard-old-build" plugin where you can specify how many builds you want to keep and all older builds are discarded.
https://github.com/jenkinsci/discard-old-build-plugin

The best part of using this plugin is that the configuration settings allow for builds to be discarded based on age, quantity, intervals of these properties, status, log file size and expressions parsed from log files.

Resource Consulted: https://stackoverflow.com/