Managing Jenkins URL and security - Commands & Configuration

Introduction

Jenkins is a tool that helps automate tasks like building and testing software. Managing its URL and security settings ensures only the right people can access it safely and that the web address is correct for users.

When you want to change the web address Jenkins uses to be easier to remember or fit your company domain

When you need to secure Jenkins so only authorized users can access it

When you want to enable HTTPS to encrypt data between users and Jenkins

When you want to disable anonymous access to protect your build jobs

When you want to configure security settings after installing Jenkins for the first time

Commands

Open the Jenkins default configuration file to change the Jenkins URL and port settings.

Terminal

sudo vi /etc/default/jenkins

Expected Output

No output (command runs silently)

Restart Jenkins to apply the changes made to the configuration file.

Terminal

sudo systemctl restart jenkins

Expected Output

● jenkins.service - Jenkins Continuous Integration Server

   Loaded: loaded (/lib/systemd/system/jenkins.service; enabled; vendor preset: enabled)

   Active: active (running) since Fri 2024-06-14 10:00:00 UTC; 5s ago

 Main PID: 1234 (java)

    Tasks: 30 (limit: 4915)

   Memory: 200.0M

   CGroup: /system.slice/jenkins.service

           └─1234 /usr/bin/java -jar /usr/share/jenkins/jenkins.war

Allow traffic on port 8080, which is the default Jenkins port, so users can access Jenkins through the firewall.

Terminal

sudo ufw allow 8080

Expected Output

Rule added

Rule added (v6)

Edit Jenkins main configuration file to enable security settings like disabling anonymous access and enabling user authentication.

Terminal

sudo vi /var/lib/jenkins/config.xml

Expected Output

No output (command runs silently)

Restart Jenkins again to apply the security configuration changes.

Terminal

sudo systemctl restart jenkins

Expected Output

● jenkins.service - Jenkins Continuous Integration Server

   Loaded: loaded (/lib/systemd/system/jenkins.service; enabled; vendor preset: enabled)

   Active: active (running) since Fri 2024-06-14 10:05:00 UTC; 5s ago

 Main PID: 1234 (java)

    Tasks: 30 (limit: 4915)

   Memory: 200.0M

   CGroup: /system.slice/jenkins.service

           └─1234 /usr/bin/java -jar /usr/share/jenkins/jenkins.war

Key Concept

If you remember nothing else, remember: changing Jenkins URL and security settings requires editing config files and restarting Jenkins to apply changes safely.

Common Mistakes

Changing Jenkins URL without restarting the Jenkins service

Jenkins will continue running with old settings until restarted, so changes won't take effect.

Always restart Jenkins after changing URL or port settings.

Not allowing Jenkins port through the firewall

Users cannot access Jenkins even if it is running because the firewall blocks the traffic.

Open the Jenkins port (default 8080) in the firewall to allow user access.

Disabling security without setting up user authentication

This leaves Jenkins open to anyone, risking unauthorized access and changes.

Enable security and configure user authentication before disabling anonymous access.

Summary

Edit /etc/default/jenkins to change Jenkins URL and port.

Restart Jenkins service to apply URL and port changes.

Open Jenkins port in firewall to allow access.

Edit /var/lib/jenkins/config.xml to enable security settings.

Restart Jenkins again to apply security changes.