# How to migrate Jenkins to "code"? **URL:** \ **Category:** Using Jenkins\ **Tags:** question\ **Created:** [August 10, 2023, 11:07am UTC](https://community.jenkins.io/t/how-to-migrate-jenkins-to-code/8985 "2023-08-10T11:07:48Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![dracorp](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/dracorp/32/1802_2.png) [@dracorp](https://community.jenkins.io/u/dracorp)\ **Post date:** [August 10, 2023, 11:07am UTC](https://community.jenkins.io/t/how-to-migrate-jenkins-to-code/8985/1 "2023-08-10T11:07:48Z")
I have a prepared ansible playbook to install Jenkins on new VMs: - prepare filesystem - technical account(s) - base repository - required OS packages - Jenkins base configuration for systemd mainly - base plugins Is there a way to dump active Jenkins to a code? I would like to copy current configuration to a code, not necessarily ansible. I would like to easily install Jenkins on VMs with a similar configuration. What’s the best way to go about it? Ultimately, maybe this is the direction I would like to go: [Configuration as Code](https://plugins.jenkins.io/configuration-as-code/) Best regards, Piotr ---
**Author:** ![Nux](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/nux/32/5165_2.png) [@Nux](https://community.jenkins.io/u/Nux)\ **Post date:** [August 25, 2023, 4:18pm UTC](https://community.jenkins.io/t/how-to-migrate-jenkins-to-code/8985/2 "2023-08-25T16:18:34Z")
Most of the time you wouldn’t want to duplicate Jenkins installations. Why? Because some tasks are scheduled, and you probably don’t want the same job schedules to run multiple times (on muliple jenkins installations). - If you want to create a **backup of jobs** then you just need to copy `config.xml` from each job (this will not include artifacts etc). - If you want a create a **backup of jenkins** configuration then you’ll need to backup main `config.xml` as well as other files (probably except for `workspace` and `jobs`). - If you want to run **multiple instances of Jenkins** then you probably want to create Nodes. In which case Jenkins will install most things for you (e.g. will install Java so you can execute Maven build and tests). ---
**Author:** ![dracorp](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/dracorp/32/1802_2.png) [@dracorp](https://community.jenkins.io/u/dracorp)\ **Post date:** [February 14, 2024, 12:44pm UTC](https://community.jenkins.io/t/how-to-migrate-jenkins-to-code/8985/3 "2024-02-14T12:44:59Z")
I’m stupid. After installing casc the option to download the configuration appears. But I have a problem with casc. Sometimes it works, sometimes no. On the latest LTS Jenkins version with a set of plug-ins: ```auto 2024-02-14 12:23:50.693+0000 [id=102] WARNING h.ExpressionFactory2$JexlExpression#evaluate: Caught exception evaluating: it.stackTraceString in /. Reason: java.lang.reflect.InvocationTargetException java.lang.IllegalStateException: Jenkins.instance is missing. Read the documentation of Jenkins.getInstanceOrNull to see what you are doing wrong. at jenkins.model.Jenkins.get(Jenkins.java:819) at io.jenkins.plugins.casc.impl.configurators.DataBoundConfigurator.getDescriptor(DataBoundConfigurator.java:229) at io.jenkins.plugins.casc.impl.configurators.DataBoundConfigurator.getName(DataBoundConfigurator.java:217) at io.jenkins.plugins.casc.ConfiguratorException.getMessage(ConfiguratorException.java:103) at java.base/java.lang.Throwable.getLocalizedMessage(Throwable.java:397) at java.base/java.lang.Throwable.toString(Throwable.java:496) at hudson.Functions.doPrintStackTrace(Functions.java:1753) at hudson.Functions.doPrintStackTrace(Functions.java:1744) at hudson.Functions.doPrintStackTrace(Functions.java:1744) at hudson.Functions.doPrintStackTrace(Functions.java:1744) at hudson.Functions.doPrintStackTrace(Functions.java:1744) at hudson.Functions.doPrintStackTrace(Functions.java:1744) at hudson.Functions.printThrowable(Functions.java:1727) ``` @Nux Yes, I want to duplicate Jenkins instance/installation. In short, I need additional Jenkins to: - testing new version, plug-ins - to switch to the stable version of Jenkins production Sometimes after an upgrade of Jenkins, more plug-ins, Jenkins doesn’t get up or something doesn’t work as it should. ---
**Author:** ![Nux](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/nux/32/5165_2.png) [@Nux](https://community.jenkins.io/u/Nux)\ **Post date:** [February 15, 2024, 12:44pm UTC](https://community.jenkins.io/t/how-to-migrate-jenkins-to-code/8985/4 "2024-02-15T12:44:11Z")
In that case I would say your safest and most accurate way would be to install Jenkins on a virtual machine. And just duplicate the machine when you want to test new things. Otherwise it would be very hard to make exactly the same environment (including e.g. out going SSH connections, saved authentications etc). ---
**Author:** ![MarkEWaite](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/markewaite/32/20_2.png) [@MarkEWaite](https://community.jenkins.io/u/MarkEWaite)\ **Post date:** [February 15, 2024, 12:55pm UTC](https://community.jenkins.io/t/how-to-migrate-jenkins-to-code/8985/5 "2024-02-15T12:55:29Z")
> [@dracorp](#): > > `it.stackTraceString` I regularly use segments from the configuration as code “View configuration” to update the container image that I use to make [my test environment](https://github.com/MarkEWaite/docker-lfs/tree/lts-jdk21-with-plugins) portable across multiple machines. I’ve been doing that successfully for several years. Others have been doing similar things for even longer. The configuration as code page on the Jenkins controller says: > Export is not intended to offer a directly usable jenkins.yaml configuration. It can be used for inspiration writing your own, be aware export can be partial, or fail for some components. > [@dracorp](#): > > I want to duplicate Jenkins instance/installation. In short, I need additional Jenkins to: > > - testing new version, plug-ins > - to switch to the stable version of Jenkins production Those are some of the reasons why I use configuration as code as well. I also use it to test new JDK versions and to test new Jenkins releases and to test large scale administrative changes. It works great for all those things. I disagree with the recommendation from @Nux because I find it easier to represent a Jenkins controller as a container image than as a virtual machine. Both can be done, but container definition is easier for me than virtual machine definition. ---
**Author:** ![dracorp](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/dracorp/32/1802_2.png) [@dracorp](https://community.jenkins.io/u/dracorp)\ **Post date:** [February 18, 2024, 10:45pm UTC](https://community.jenkins.io/t/how-to-migrate-jenkins-to-code/8985/6 "2024-02-18T22:45:48Z")
> [@MarkEWaite](#): > > Those are some of the reasons why I use configuration as code as well. I also use it to test new JDK versions and to test new Jenkins releases and to test large scale administrative changes. It works great for all those things. > > I disagree with the recommendation from @Nux because I find it easier to represent a Jenkins controller as a container image than as a virtual machine. Both can be done, but container definition is easier for me than virtual machine definition. I also agree. For me, JCAsC would be a big improvement. But, I do not know why, in some cases, this plugin does not work on my Jenkins installation. Interestingly, on others, it works. I don’t know if the plugin itself is messing something up, or more a set of plugins, some conflict between plugins. I have another problem that I recently noticed. During migration, API user tokens are not copied by me. Where does Jenkins keep the API user tokens? In the file /users/user/config.xml I have: ```auto uuid name 2024-01-24 18:39:53.435 UTC 11 hash ``` All secret\* files are the same on both Jenkins, but I can only see the API token on one. Reference: [Ability to preconfigure an API token via JCasC · Issue #1830 · jenkinsci/configuration-as-code-plugin · GitHub](https://github.com/jenkinsci/configuration-as-code-plugin/issues/1830) I can create a token, but I don’t know how to migrate all users’ tokens by copying a file or files. ---
**Author:** ![dracorp](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/dracorp/32/1802_2.png) [@dracorp](https://community.jenkins.io/u/dracorp)\ **Post date:** [February 18, 2024, 10:48pm UTC](https://community.jenkins.io/t/how-to-migrate-jenkins-to-code/8985/7 "2024-02-18T22:48:30Z")
> [@Nux](#): > > In that case I would say your safest and most accurate way would be to install Jenkins on a virtual machine I’m using VMs for that. But I don’t have access to a hypervisor. I am aware that I will not duplicate everything.