Solution
In Java, between Java 8 to 12. It supports only Java 8 and 11. Java 9 and 10 are not supported.https://www.jenkins.io/doc/administration/requirements/java/#java-requirements
Solution
Minimum 256MB of RAM required to run Jenkins.https://www.jenkins.io/doc/book/installing/linux/#prerequisites
Solution
Yes, we can install Jenkins on Windows.https://www.jenkins.io/doc/book/installing/windows/#windows
Solution
Default path is /var/lib/jenkins/secrets/.https://www.jenkins.io/doc/book/installing/linux/#unlocking-jenkins
Solution
Default path is /var/jenkins_home/secrets/.https://www.jenkins.io/doc/book/installing/docker/#unlocking-jenkins
Solution
(a.) OS native packages (RPM, DEB ...)/Windows (MSI Installer) (b.) WAR (Web Application Archive/Web Application Resource) File (c.) Docker Image (d.) Cloud Templates (Azure, AWS, GCP)https://www.jenkins.io/download/#downloading-jenkins
What is the location of the file where we can change default Jenkins user, log, home and arguments to pass to Jenkins such as --httpListenAddress, --httpPort?
Solution
It is a /etc/default/jenkins or /etc/sysconfig/jenkins.https://support.cloudbees.com/hc/en-us/articles/209715698-How-to-add-Java-arguments-to-Jenkins-#traditionalplatform
Solution
It is a /etc/default/jenkins or /etc/sysconfig/jenkins.https://support.cloudbees.com/hc/en-us/articles/209715698-How-to-add-Java-arguments-to-Jenkins-#debianubuntubasedlinuxdistributions
Solution
It's a /var/lib/jenkins.https://www.jenkins.io/doc/book/installing/linux/#unlocking-jenkins
https://docs.cloudbees.com/docs/admin-resources/latest/backup-restore/jenkins-home
https://wiki.jenkins.io/display/JENKINS/Administering+Jenkins
Solution
No, Microsoft .NET Framework 2.0 support removed in Jenkins version 2.249.1. Actually starting from Jenkins version 2.238, .NET Framework 4.0 or above is required for all Windows service installations and built-in Windows service management logic.https://www.jenkins.io/doc/upgrade-guide/2.249/#upgrading-to-jenkins-lts-2-249-1
Solution
Before Jenkins version 2.238, .NET Framework 2.0 was supported.https://www.jenkins.io/doc/administration/requirements/windows/#net-requirements
Solution
It's a %JENKINS_HOME% of User home directory.https://www.jenkins.io/blog/2020/08/12/windows-installers-upgrade/#road-forward
Solution
(a.) Install suggested plugins (b.) Select plugins to installhttps://www.jenkins.io/doc/book/installing/windows/#customizing-jenkins-with-plugins
Solution
No, e-mail ID is required while adding name of user, password, e-mail. Otherwise it will give an error.WAR file based installation of Jenkins can be run as a stand-alone application in a servlet container?
Solution
Yes, It's run as a stand-alone application in a servlet container.$ java ${JAVA_OPTS} -jar jenkins.war ${JENKINS_OPTS}
Note: If you misspell in command line parameters, Jenkins ignores it rather than generating an error.
https://www.jenkins.io/doc/book/installing/#installing-jenkins
https://www.jenkins.io/doc/book/installing/initial-settings/#jenkins-parameters
During POST-INSTALLATION WIZARD process, What kind of three instructions you will see when you access Jenkins from the browser for the first time?
Solution
(a.) Unlock Jenkins (b.) Install essential plugins (Customize Jenkins Plugins) (c.) Create first admin userhttps://www.jenkins.io/doc/book/installing/windows/#setup-wizard
Solution
Yes, we can modify the default Jenkins URL before viewing the Jenkins Dashboard. If we'll not modify that time then we have to go to Manage Jenkins > Configure System > Jenkins Location Section.https://stackoverflow.com/a/17711268/12522533
https://wiki.jenkins.io/display/JENKINS//Starting+and+Accessing+Jenkins
Solution
Yes, You can install the additional plugins anytime. You have to go into the Manage Jenkins > Manage Plugins aka Plugin Manager.You will see Updated, Available, Installed and Advanced Section.
https://www.jenkins.io/doc/book/managing/plugins/#installing-a-plugin
Solution
Name of the root configuration file of Jenkins is config.xml and location path is /var/lib/jenkins/config.xml and common for all Linux distributions.https://jenkins-le-guide-complet.github.io/html/sec-hudson-home-directory-contents.html
Solution
Path is /var/lib/jenkins/plugins/.Solution
Path is /var/lib/jenkins/jobs/.Solution
Path is /var/lib/jenkins/users/.Solution
java -jar jenkins.warIf you don't want to run the Jenkins on default port 8080 and wants to run on port 9595 then specify --httpPort flag.
java -jar jenkins.war --httpPort=9595
https://www.jenkins.io/doc/book/installing/war-file/#run-the-war-file
Solution
That's builds process.Solution
(a.) "Spanned volume" on Windows (b.) "LVM" on LinuxWhat is the most common command line flags which we can use with java -jar jenkins.war ${JENKINS_OPTIONS} for Jenkins?
Solution
Jenkins Flags/Options:--prefix (default: /), --httpPort (default: 8080), --httpListenAddress (default: 0.0.0.0), --logfile
java ${JAVA_OPTIONS} -jar jenkins.war ${JENKINS_OPTIONS}
Solution
java -jar jenkins.war --httpPort=8085 --prefix=/apps --httpListenAddress=127.0.0.1After that we can access in the browser url http://127.0.0.1:8085/apps
https://www.jenkins.io/doc/book/installing/initial-settings/#configuring-http
Solution
Yes, we can install Jenkins in a Docker container and Kubernetes Pod's container.https://www.jenkins.io/doc/book/installing/docker/
https://hub.docker.com/r/jenkins/jenkins/
https://www.jenkins.io/doc/book/installing/kubernetes/
Solution
In generally three ways:(a.) By setting Environment Variable (b.) By setting System Property (c.) By setting JNDI (Java Naming and Directory Interface) Environment
We can also set in ~/.jenkins for system configuration. It's appear in the User's home directory when we install Jenkins from WAR file.
https://wiki.jenkins.io/display/JENKINS/Administering+Jenkins
Solution
That's Manage Jenkins section.https://jenkins-le-guide-complet.github.io/html/sect-installation-upgrading.html
Solution
Prepare for Shutdown is initiate to a graceful shutdown of Jenkins. It's ensure that no jobs build during shutdown.It's available in the Manage Jenkins > Prepare for Shutdown.
We can do gracefully shutdown from the browser also.
http://127.0.0.1:8080/quietDown
We can perform restart and exit as well.
https://support.cloudbees.com/hc/en-us/articles/216118748-How-to-Start-Stop-or-Restart-your-Instance-
During the process of upgrading Jenkins, to the next available version. What is the default location of jenkins.war file on Linux systems to replace with the new one?
Solution
Path is /usr/share/jenkins/ on Linux systems.After replace with the new WAR file, restart the Jenkins service to apply the upgrades.
Solution
We can write information in the System Message Box, which is located at Manage Jenkins > Configure System section.As we know that the Global System Message in Jenkins clearly indicates that this message should only be shown on the "top of our Jenkins home page". So we can use this option.
Solution
We can configure Security, JDK Installations, Version Control Tools (Git), Build Tools (Ant, Gradle and Maven), Global properties, Jenkins location, e-mail notification, Plugin configurations.System Configuration is located at Manage Jenkins.
Solution
Make it Executor count to 0.Solution
It's contain .hpi extension.Solution
We can install plugins on the master controller via (a.) Using the "Plugin Manager" in the Web UI. (b.) Using the Jenkins CLI install-plugin command.https://www.jenkins.io/doc/book/managing/plugins/#installing-a-plugin
Solution
Yes, we can install plugins from .hpi file. You have to go to the Manage Jenkins > Manage Plugins page in the web UI.Click on the Advanced tab, then upload the plugin file under the Upload Plugin section.
https://www.jenkins.io/doc/book/managing/plugins/#advanced-installation
Solution
Yes, we can install already downloaded plugin files (.hpi). We have to put the .hpi plugin file into the JENKINS_HOME/plugins/ path. In common cases, it's /var/lib/jenkins/plugins/.https://www.jenkins.io/doc/book/managing/plugins/#on-the-master
Solution
Go into the Manage Jenkins > Manage Plugins then click on the Updates tab and update the required plugins.By default, on the master controller - Jenkins will check for updates from the Update Center once every 24 hours. To manually trigger a check for updates, simply click on the Check now button in the Updates tab.
Solution
You have to go into the Manage Jenkins > Manage Plugins > Advanced tab.https://wiki.jenkins.io/display/JENKINS/JenkinsBehindProxy
Solution
We can check installed plugins in three ways, (a.) Manage Plugins (b.) System Information both are located at Manage Jenkins and (c.) In the $JENKINS_HOME/plugins/ (/var/lib/jenkins/plugins/) on the host system.https://www.jenkins.io/doc/book/managing/plugins/
What is the two options we will get in the Post-installation setup wizard to install plugins in the installation of Jenkins?
Solution
(a.) Install suggested plugins, which are based on common use cases. (b.) Select plugins to install, which are used to install set of plugins not all suggested plugins. By default, it selected all the suggested/common plugins in the Select plugins to install section. We have to do untick which we don't want to install.https://www.jenkins.io/doc/book/installing/linux/#customizing-jenkins-with-plugins
Solution
It's located at Manage Jenkins > Configure System. By default, it sets to 2. There is no fix number to set maximum number of executor.https://support.cloudbees.com/hc/en-us/articles/216456477-What-is-a-Jenkins-Executor-and-how-can-I-best-utilize-my-executors
https://support.cloudbees.com/hc/en-us/articles/115002654991-Remoting-Best-Practices#numberofexecutors
Solution
Defaults to 0.Quiet Period : Provide a gaps between builds. In the queue, Build A and Build B. We set quiet period to 2min so after successful Build A, process will take a break of 2min to start build for Build B.
https://www.jenkins.io/blog/2010/08/11/quiet-period-feature/
Solution
Lists are : Subversion, Mercurial, Perforce, Team Foundation Server (TFS), GitHub, Concurrent Versions System (CVS), REPO, GitLab, P4, Bitbucket, ClearCase etc.https://devops.stackexchange.com/a/22
Solution
It consumes XML test reports which is generated during the builds and provides us graphical visualization of the test reports.https://www.jenkins.io/doc/pipeline/steps/junit/#junit-plugin
https://wiki.jenkins.io/display/JENKINS/JUnit+graph
Solution
After installation and configuration of this xUnit plugin, Jenkins can transform test result reports produced by different testing tools into JUnit test result format. Under the hood it helps to display the test results.https://www.jenkins.io/doc/pipeline/steps/xunit/#xunit-plugin
https://www.jenkins.io/blog/2016/10/31/xunit-reporting/
https://plugins.jenkins.io/xunit/
Solution
Go into the Manage Jenkins > Manage Plugins (PluginManager) > Advanced tab after that at the bottom we can see Update Site section. Update with the new site URL.https://updates.jenkins.io/
Solution
Jenkins added a query parameter ?version to the update site URL for a specific version number. So format is:https://updates.jenkins.io/update-center.json?version=2.263.1
We specified version number to look only for that version specific updates not for all (version) one which is available in the Update Center.
https://updates.jenkins.io/#version-specific-update-sites
Solution
Timestamper plugin based. By default, It's not available in the Jenkins instance. We have to install its plugin. It's used to define Time Format.https://www.jenkins.io/doc/pipeline/steps/timestamper/
Solution
In the Manage Jenkins > Configure System > Jenkins Location.Solution
It's store in the file hudson.model.UpdateCenter.xml. Which is located in the path /var/lib/jenkins/ in Linux distribution. May be different as per installation process. We can add/update Update Site URL into that file also and restart the Jenkins service after made changes.https://stackoverflow.com/a/37989185/12522533
Solution
Yes, we can install multiple versions of JDK package in the system as per use cases through Jenkins Web UI.Go into the Manage Jenkins > Global Tool Configuration > JDK.
We can also install JDK from Oracle site and locally available archive file. All different kind of options are available in the Add Installer tab.
https://www.jenkins.io/doc/administration/requirements/upgrade-java-guidelines/
https://plugins.jenkins.io/jdk-tool/
Solution
Yes, We have to tick mark the option to Install automatically in the Manage Jenkins > Global Tool Configuration > Maven.First Maven plugin should be installed and configured to use.
We can install direct from the Apache site or locally available archive file. All different kind of options are available in the Add Installer tab.
Solution
Yes, it's possible via Reload Configuration from Disk option. It's located in the bottom at Manage Jenkins.Highlighted section - Tools and Actions.
https://support.cloudbees.com/hc/en-us/articles/209691677-What-does-Reload-Configuration-from-Disk-do
In the Manage Plugins, installed plugin section a few of the plugins are blocked (cannot be disabled/uninstall). What is the reason behind that?
Solution
Because they have one or more enabled dependents. For an e.g. Pipeline: Groovy dependent on Pipeline, Pipeline: Declarative, Pipeline: Shared Groovy Libraries, Pipeline: Multibranch, Pipeline: Declarative Extensions Points API etc.Solution
The original project name is Hudson and renamed into Jenkins in 2011.Solution
Version Control System (VCS).https://www.cloudbees.com/blog/source-code-management-more-just-git
Solution
No, It's available after installed and configured respective VCS plugin.Solution
Through Source Code Management > Build Triggers > Poll SCM. We have to set the schedule in Poll SCM to check in every sec/min/hr/day/week/month.Format is based on the cron. (* * * * *)
https://crontab.guru/
https://stackoverflow.com/q/10121098/12522533
Solution
Unit testing, integration testing, and smoke testingWhat is the name of testing, which can be run in the same order, parallel and define different tests to run at different stages?
Solution
It's Unit tests.Solution
current versions of Linux/Windows/macOS/Unix|BSD, Java 8 or 11, Jenkins LTS runs on Java 11 in Release 2.164.1 or newer.Solution
Java Virtual Machine (JVM) must be tuned:Memory Heap size: -Xms1G -Xmx2G
G1 garbage collector for heap > 4GB : -XX:+UseG1GC
-XX:+UseG1GC: enables the G1 Garbage Collector
https://docs.cloudbees.com/docs/admin-resources/latest/jvm-troubleshooting/#suggested-specifications
Solution
Operating system limits max number of open files, max number of forked processes, network tuning (packet size, TCP timeouts).Solution
When we start to build the host jobs and due to distance of host, it increases files size. Because Jenkins writes a lot of files (Artifacts, logs and other files) as it processes builds.Solution
In Jenkins, bigger disk is good but low latency SSD disk is perfect.Solution
Artifacts, logs and other files (tmp/xml).Solution
Yes, We can. But must have enough space on the disk to accommodate the backed up files.Instead of create a separate filesystem for the backup directory.
Solution
Spanned volume on Windows.LVM on Linux but not recommended for initial level because have to do upfront planning for this.
https://www.jenkins.io/doc/book/scaling/architecting-for-scale/#scalable-storage-for-master
Solution
Aborted: Interrupted before it reaches its expected end.Failed: Failed due to fatal error.
Stable: The Build was Successful and no Publisher reports it as Unstable.
Successful: No compilation errors.
Unstable: The Build had some errors but they were not fatal. A Build is unstable if it was built successfully and one or more publishers report it unstable.
https://www.jenkins.io/doc/book/glossary/#build-status
Solution
You have to move into the Manage Jenkins > Configure System, after drop down you will see Jenkins Location where you have to set the new URL in Jenkins URL. URL should be ideal/easy.Which section covers the controlling or restriction access to third party sites and applications through credentials?
Solution
It's a Manage Jenkins > Configure Credential Providers.Like Artifact Repositories, Cloud-based Storage Systems, Services and so on.
https://www.jenkins.io/doc/book/using/using-credentials/#using-credentials
Solution
Secret text: A token such as an API token (e.g. a GitHub personal access token).Username and password: Which could be handled as separate components or as a colon separated string in the format username:password. (e.g. david:s8*4123dhf)
Secret file: Which is essentially secret content in a file.
SSH Username with private key: An SSH public/private key pair.
Certificate: A PKCS#12 Certificate file and optional Password.
Docker Host Certificate Authentication credentials.
Solution
You have to move into the Manage Jenkins > Script Console.Scripts execute in a Groovy Sandbox that limits the internal APIs that are accessible. To secure unsafe method to display result in the Jenkins environment, Admin can use Script Security Plugin.
https://www.jenkins.io/doc/book/managing/script-console/#script-console
Solution
Manage Jenkins > Manage Nodes and Cloudshttps://wiki.jenkins.io/display/JENKINS/Distributed+builds
Where can we add/delete/modify user to the Jenkins User Database and lists all the users who are in that Database?
Solution
Go into the Manage Jenkins > Manage Usershttps://wiki.jenkins.io/display/jenkins/standard+security+setup
Solution
Agenthttps://support.cloudbees.com/hc/en-us/articles/216456477-What-is-a-Jenkins-Executor-and-how-can-I-best-utilize-my-executors
Solution
We can set the executors in the multiple locations, which are : Manage Jenkins > Configure System and Manage Jenkins > Manage Nodes and Clouds (in the Node's Configure Settings)Solution
It's a Manage Jenkins > Load Statistics.Solution
In the System Log from the Manage Jenkins.It doesn't contain build logs.
https://www.jenkins.io/doc/book/system-administration/viewing-logs/
Solution
Move into the Manage Jenkins > System Log > Add New Log Recorder.https://www.jenkins.io/doc/book/system-administration/viewing-logs/#logs-in-jenkins
Solution
Number of online executors.Number of busy executors.
Number of available executors.
Queue length (number of jobs that are waiting for an available executor).
Where can you see the list of system properties, environmental variables, memory usages, thread dumps and plugins all at once in the Jenkins?
Solution
You can see from the Manage Jenkins > System Information.System Properties that can be used as arguments to the command line to start Jenkins and Environment Variables with current values.
Solution
In the Manage Jenkins > Manage Plugins under the installed tab and in the Manage Jenkins > System Information under the Plugins section.Solution
In the Manage Jenkins > About Jenkins page.Solution
In the Manage Jenkins > About Jenkins page.Solution
In the Manage Jenkins > About Jenkins page. Contain links of all third-party dependencies for each plugins.Solution
It's located at Manage Jenkins > Jenkins CLI. It's used to access and manage Jenkins from a shell or from a script.https://www.jenkins.io/doc/book/managing/cli/
Solution
Go into the Manage Jenkins > Manage Old data.https://www.jenkins.io/doc/book/managing/plugins/#removing-old-data
Solution
.hpi or .jpi extension.https://stackoverflow.com/questions/30658375/what-is-difference-between-hpi-and-jpi-of-jenkins-plugins
Solution
Option is --pluginroot.https://support.cloudbees.com/hc/en-us/articles/115000486312-CloudBees-CI-CloudBees-Core-Performance-Best-Practices-for-Linux#jenkinshomesharedstorage
Solution
From Jenkins GUI, it's not possible. Instead, we have to install the old version or different version after that put the .hpi plugin file into the path $JENKINS_HOME/plugins.https://www.jenkins.io/doc/book/managing/plugins/#on-the-master
What is the mean of greyed-out check marks and no uninstall button for plugins in the Installed tab from the Manage Plugins?
Solution
That's means that are required by other plugins.Solution
Yes, plugin continues to function until you restart Jenkins.After a restart, plugin does not appear in the Jenkins GUI and all extensions it contributed disappear.
https://wiki.jenkins.io/display/JENKINS/Removing+and+disabling+plugins
Solution
No, it will not remove that configuration files. We can use Manage Old Data page to remove those configuration files left by an uninstalled plugin.Solution
Yes, we can remove .hpi or .jpi file from the $JENKINS_HOME/plugins directory to remove/uninstall the plugin.*.jpi.disabled or *.hpi.disabled files available in the $JENKINS_HOME/plugins directory. What is the meaning of that file in Jenkins?
Solution
That means the plugin is disabled and contains suffix .disabled at the end of the plugin file.https://support.cloudbees.com/hc/en-us/articles/204323074-How-to-disable-a-plugin-when-Jenkins-is-down-
Solution
We can choose the Manage Jenkins > Manage Old Data page to clean up those configuration files.https://www.jenkins.io/doc/book/managing/plugins/#removing-old-data
Solution
Through email, slack and SMS notifications etc. Many third party plugins are available to send notification messages.https://www.cloudbees.com/blog/sending-notifications-pipeline
https://www.jenkins.io/blog/2017/02/15/declarative-notifications/
Solution
Yes, we can create nested subfolders in the Jenkins.https://docs.cloudbees.com/docs/admin-resources/latest/plugins/folder
Solution
By default, logs are available in /var/log/jenkins/jenkins.log.Log location can be customized:
In /etc/default/jenkins (for *.deb)
In /etc/sysconfig/jenkins (for *.rpm)
https://www.jenkins.io/doc/book/system-administration/viewing-logs/#viewing-logs
Solution
By default logs should be at %JENKINS_HOME%/jenkins.out and %JENKINS_HOME%/jenkins.errLog location can be customized:
In %JENKINS_HOME%/jenkins.xml
https://www.jenkins.io/doc/book/system-administration/viewing-logs/#windows
Solution
In the Manage Jenkins > System Log.https://www.jenkins.io/doc/book/system-administration/viewing-logs/#logs-in-jenkins
Solution
In the Manage Jenkins > System Log > New Log Recorder.Path is http://localhost:8080/log/new
To monitor the server loads and displays a graph of the server load time for the master node which four metrics should be consider?
Solution
Number of online executors, Number of busy executors, Number of available executors and Queue length.Solution
some of the popular ones are:Monitoring, Disk Usage and Build Monitor.
https://www.jenkins.io/doc/book/system-administration/monitoring/
Solution
Freestyle projectSolution
To configure into the main configuration file under the $JENKINS_HOME/jobs/[JOB_NAME]/config.xml.https://www.jenkins.io/doc/book/managing/system-properties/#jenkins-model-jenkins-buildsdir