--- stage: Manage group: Integrations info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/product/ux/technical-writing/#assignments --- # Jenkins **(FREE)** > [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/246756) to GitLab Free in 13.7. You can trigger a build in Jenkins when you push code to your repository or create a merge request in GitLab. The Jenkins pipeline status displays on merge requests widgets and on the GitLab project's home page. For an overview of the Jenkins integration for GitLab, see [GitLab workflow with Jira issues and Jenkins pipelines](https://youtu.be/Jn-_fyra7xQ). Use the Jenkins integration when: - You plan to migrate your CI from Jenkins to [GitLab CI/CD](../ci/index.md) in the future, but need an interim solution. - You're invested in [Jenkins plugins](https://plugins.jenkins.io/) and choose to keep using Jenkins to build your apps. NOTE: This documentation focuses only on how to configure a Jenkins *integration* with GitLab. Learn how to set up Jenkins [on your local machine](../development/integrations/jenkins.md) in the developer documentation, and how to migrate from Jenkins to GitLab CI/CD in the [Migrating from Jenkins](../ci/migration/jenkins.md) documentation. The Jenkins integration requires configuration in both GitLab and Jenkins. ## Grant Jenkins access to the GitLab project To grant Jenkins access to the GitLab project: 1. Create a personal, project, or group access token. - [Create a personal access token](../user/profile/personal_access_tokens.md#create-a-personal-access-token) to use the token for all Jenkins integrations of that user. - [Create a project access token](../user/project/settings/project_access_tokens.md#create-a-project-access-token) to use the token at the project level only. For instance, you can revoke the token in a project without affecting Jenkins integrations in other projects. - [Create a group access token](../user/group/settings/group_access_tokens.md#create-a-group-access-token-using-ui) to use the token for all Jenkins integrations in all projects of that group. 1. Set the access token scope to **API**. 1. Copy the access token value to [configure the Jenkins server](#configure-the-jenkins-server). ## Configure the Jenkins server Install and configure the Jenkins plugin. The plugin must be installed and configured to authorize the connection to GitLab. 1. On the Jenkins server, select **Manage Jenkins > Manage Plugins**. 1. Install the [Jenkins GitLab Plugin](https://wiki.jenkins.io/display/JENKINS/GitLab+Plugin). 1. Select **Manage Jenkins > Configure System**. 1. In the **GitLab** section, select **Enable authentication for '/project' end-point**. 1. Select **Add**, then choose **Jenkins Credential Provider**. 1. Select **GitLab API token** as the token type. 1. In **API Token**, [paste the value you copied from GitLab](#grant-jenkins-access-to-the-gitlab-project) and select **Add**. 1. Enter the GitLab server's URL in **GitLab host URL**. 1. To test the connection, select **Test Connection**. ![Jenkins plugin configuration](img/jenkins_gitlab_plugin_config.png) For more information, see [Jenkins-to-GitLab authentication](https://github.com/jenkinsci/gitlab-plugin#jenkins-to-gitlab-authentication). ## Configure the Jenkins project Set up the Jenkins project you intend to run your build on. 1. On your Jenkins instance, go to **New Item**. 1. Enter the project's name. 1. Select **Freestyle** or **Pipeline** and select **OK**. We recommend a Freestyle project, because the Jenkins plugin updates the build status on GitLab. In a Pipeline project, you must configure a script to update the status on GitLab. 1. Choose your GitLab connection from the dropdown list. 1. Select **Build when a change is pushed to GitLab**. 1. Select the following checkboxes: - **Accepted Merge Request Events** - **Closed Merge Request Events** 1. Specify how the build status is reported to GitLab: - If you created a **Freestyle** project, in the **Post-build Actions** section, choose **Publish build status to GitLab**. - If you created a **Pipeline** project, you must use a Jenkins Pipeline script to update the status on GitLab. Example Jenkins Pipeline script: ```groovy pipeline { agent any stages { stage('gitlab') { steps { echo 'Notify GitLab' updateGitlabCommitStatus name: 'build', state: 'pending' updateGitlabCommitStatus name: 'build', state: 'success' } } } } ``` For more Jenkins Pipeline script examples, go to the [Jenkins GitLab plugin repository on GitHub](https://github.com/jenkinsci/gitlab-plugin#scripted-pipeline-jobs). ## Configure the GitLab project Configure the GitLab integration with Jenkins in one of the following ways. ### Configure a Jenkins integration (recommended) GitLab recommends this approach for Jenkins integrations because it is easier to configure than the [webhook integration](#configure-a-webhook). 1. On the top bar, select **Main menu > Projects** and find your project. 1. On the left sidebar, select **Settings > Integrations**. 1. Select **Jenkins**. 1. Select the **Active** checkbox. 1. Select the events you want GitLab to trigger a Jenkins build for: - Push - Merge request - Tag push 1. Enter the **Jenkins server URL**. 1. Optional. Clear the **Enable SSL verification** checkbox to disable [SSL verification](../user/project/integrations/index.md#manage-ssl-verification). 1. Enter the **Project name**. The project name should be URL-friendly, where spaces are replaced with underscores. To ensure the project name is valid, copy it from your browser's address bar while viewing the Jenkins project. 1. If your Jenkins server requires authentication, enter the **Username** and **Password**. 1. To test the connection to Jenkins, select **Test settings**. 1. Select **Save changes**. ### Configure a webhook If you are unable to provide GitLab with your Jenkins server login, you can use this option to integrate GitLab and Jenkins. 1. In the configuration of your Jenkins job, in the GitLab configuration section, select **Advanced**. 1. Under **Secret Token**, select **Generate**. 1. Copy the token, and save the job configuration. 1. In GitLab, create a webhook for your project, enter the trigger URL (such as `https://JENKINS_URL/project/YOUR_JOB`) and paste the token in **Secret Token**. 1. To test the webhook, select **Test**. ## Related topics - For a real use case, read the blog post [Continuous integration: From Jenkins to GitLab using Docker](https://about.gitlab.com/blog/2017/07/27/docker-my-precious/). - See the ['GitLab vs. Jenkins' comparison page](https://about.gitlab.com/devops-tools/jenkins-vs-gitlab/) for information on how moving to a single application for the entire software development lifecycle can decrease hours spent on maintaining toolchains by 10% or more. ## Troubleshooting ### Error during GitLab configuration - "Connection failed. Please check your settings" If you get this error message while configuring GitLab, the following are possible causes: - GitLab is unable to reach your Jenkins instance at the address. If your GitLab instance is self-managed, try pinging the Jenkins instance at the domain provided on the GitLab instance. - The Jenkins instance is at a local address and is not included in the [GitLab installation's allowlist](../security/webhooks.md#allow-outbound-requests-to-certain-ip-addresses-and-domains). - The credentials for the Jenkins instance do not have sufficient access or are invalid. - The **Enable authentication for `/project` end-point** checkbox is not selected in your [Jenkins plugin configuration](#configure-the-jenkins-server). ### Error in merge requests - "Could not connect to the CI server" You might get the `Could not connect to the CI server` error if GitLab did not receive a build status update from Jenkins via the [Commit Status API](../api/commits.md#commit-status). This issue occurs when Jenkins is not properly configured or there is an error reporting the status via the API. To fix this issue, ensure you: 1. [Configure the Jenkins server](#configure-the-jenkins-server) for GitLab API access. 1. [Configure the Jenkins project](#configure-the-jenkins-project), including the 'Publish build status to GitLab' post-build action. ### Merge request event does not trigger a Jenkins pipeline This issue can occur when the request exceeds the [webhook timeout](../user/project/integrations/webhooks.md#webhook-fails-or-multiple-webhook-requests-are-triggered), which is set to 10 seconds by default. For this issue, check: - [Integration webhook logs](../user/project/integrations/index.md#troubleshooting) for request failures. - `/var/log/gitlab/gitlab-rails/production.log` for messages like: ```plaintext WebHook Error => Net::ReadTimeout ``` or ```plaintext WebHook Error => execution expired ``` On self-managed GitLab instances, you can fix this issue by [increasing the webhook timeout value](../administration/instance_limits.md#webhook-timeout). ### Enable job logs in Jenkins To troubleshoot an integration issue, you can enable job logs in Jenkins to get more details about your builds. To enable job logs in Jenkins: 1. Go to **Dashboard > Manage Jenkins > System Log**. 1. Select **Add new log recorder**. 1. Enter a name for the log recorder. 1. On the next screen, select **Add** and enter `com.dabsquared.gitlabjenkins`. 1. Make sure that the Log Level is **All** and select **Save**. To view your logs: 1. Run a build. 1. Go to **Dashboard > Manage Jenkins > System Log**. 1. Select your logger and check the logs.