Jenkins not updating the K8S agent definition - jenkins

We have our Jenkins configured with the Kubernetes agent, defined in a yaml file. The problem is that when I try to update the yaml, Jenkins doesn't see the update and still uses the old agent template (some cache'ing?).
Job's build configuration:
Jenkinsfile-gke.groovy with the updated yaml file
pipeline {
agent {
kubernetes {
yamlFile '.jenkins/agent-pod.yaml'
...
Build's logs (the files are being obtained from the correct commit that is updating them, however the logs beneath show that the version before the chasnges is being applied):

Related

Reading config file in DSL build on agent host

I try to configure Jenkins' seed job, where whole business is in provided DSL script. I want to seperate that script from its configuration, which I want to locate in additional yml file. When I try to read that file:
#Grab('org.yaml:snakeyaml:1.17')
import org.yaml.snakeyaml.Yaml
def workDir = SEED_JOB.getWorkspace()
def config = new Yaml().load(("${workDir}/config.yml" as File).text)
I receive error
java.io.FileNotFoundException: /var/lib/jenkins/workspace/test.dsl/config.yml (No such file or directory)
I suppose that Jenkins is looking for the file on a master host, not an agent node where workspace is located.
Is it possible to read yml file in DSL build step on the agent node? Or maybe I have to execute that seed job always on my master host?
This seems not possible as the jobDsl script is executed on master. You can try force to run the job on master with label master.
From the documentation in section Script location:
Job DSL scripts are executed on the Jenkins master node, but the seed job's workspace which contains the script files may reside on a build node. This mean that direct access to the file specified by FILE may not be possible from a DSL script. See Distributed builds for details.

Triggering vSphere build via Jenkins pipeline agent

My goal is to set up a declarative pipeline job which automatically triggers the vSphere plugin to create a VM on which the build and test runs in a clean environment.
I've configured the vSphere Cloud Plugin in Jenkins' global settings to build slaves with label "appliance-slave", and this does trigger for freestyle jobs with "Restrict where this project can be run" set to that label. However, the following example pipeline never triggers the vSphere plugin (based on tailing the Jenkins log):
pipeline {
agent {
label 'appliance-slave'
}
stages {
stage('Test') {
steps {
sh "hostname && hostname -i"
}
}
}
}
I've searched the documentation without any luck. Is there some configuration option or alternate agent declaration that I'm missing that would allow this?
Finally resolved the problem; the issue was that I needed to go in to the actual slave configuration and set up the slave there. The vSphere plugin modifies the slave configuration page to allow exactly what I was trying to do: shutting down and reverting the VM once the build is complete.

What does the agent mean in jenkins?

I am trying to use jenkins. But when I reading the Declarative Pipeline Syntax, I confused by the agent term
https://jenkins.io/doc/book/pipeline/syntax/#scripted-pipeline
What does the agent stand for?
Is that mean I can set the pipeline runtime folder path?
How to create an agent?
How set a label for agent?
I can feel you :-D.
Here are the answers:
The agent section specifies where the entire Pipeline, or a specific stage, will execute in the Jenkins environment depending on where the agent section is placed. The section must be defined at the top-level inside the pipeline block, but stage-level usage is optional. - Content copied from the agent section
NO, this has nothing to do with the pipeline runtime folder path.
You can for example Create an agent/node by the following tutorial:
How to Setup Jenkins Agent/Slave Using Password and ssh Keys. -
But there are many other ways to create an agent e.g. using a Docker-Container (...).
You can Set a label under the Configuration of the Node.
You can use a label in your pipeline like:
pipeline {
agent { label 'labelName' }
(...)
}
While #adbo covered questions asked, Jenkins glossary describes agent really well:
typically a machine, or container, which connects to a Jenkins controller and executes tasks when directed by the controller.
You can choose to run entire pipeline on any available agent (agent any at the top of the pipeline) or run a specific stage on the agent of choice e.g. run build stage in a specific environ by overriding agent in that stage:
agent { docker { image 'my image' } }

Jenkins Pipeline as Code with Docker Error

For one of my projects that I have on GitHub, I wanted to build it as a docker image and push it to my docker hub. The project is a sbt one with a Scala codebase.
Here is how my JenkinsFile is defined:
#!groovy
node {
// set this in Jenkins server under Manage Jenkins > Credentials > System > Global Credentials
docker.withRegistry('https://hub.docker.com/', 'joesan-docker-hub-credentials') {
git credentialsId: '630bd271-01e7-48c3-bc5f-5df059c1abb8', url: 'https://github.com/joesan/monix-samples.git'
sh "git rev-parse HEAD > .git/commit-id"
def commit_id = readFile('.git/commit-id').trim()
println comit_id
stage "build" {
def app = docker.build "Monix-Sample"
}
stage "publish" {
app.push 'master'
app.push "${commit_id}"
}
}
}
When I tried to run this from my Jenkins server, I get the following error:
java.io.FileNotFoundException
at jenkins.plugins.git.GitSCMFile$3.invoke(GitSCMFile.java:167)
at jenkins.plugins.git.GitSCMFile$3.invoke(GitSCMFile.java:159)
at jenkins.plugins.git.GitSCMFileSystem$3.invoke(GitSCMFileSystem.java:161)
at org.jenkinsci.plugins.gitclient.AbstractGitAPIImpl.withRepository(AbstractGitAPIImpl.java:29)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.withRepository(CliGitAPIImpl.java:65)
at jenkins.plugins.git.GitSCMFileSystem.invoke(GitSCMFileSystem.java:157)
at jenkins.plugins.git.GitSCMFile.content(GitSCMFile.java:159)
at jenkins.scm.api.SCMFile.contentAsString(SCMFile.java:338)
at org.jenkinsci.plugins.workflow.cps.CpsScmFlowDefinition.create(CpsScmFlowDefinition.java:101)
at org.jenkinsci.plugins.workflow.cps.CpsScmFlowDefinition.create(CpsScmFlowDefinition.java:59)
at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:232)
at hudson.model.ResourceController.execute(ResourceController.java:98)
at hudson.model.Executor.run(Executor.java:404)
Finished: FAILURE
Since this is running inside a VM on Azure, I thought the VM was not able to reach outside, but that seems not to be the case as I was able to ssh into the VM and git pull from the Git repo. So what is the problem here? How could I make this work?
for me unchecking "lightweight checkout" fixed the issue
I experienced the exact same error. My setting:
Pipeline build inside a dockerized Jenkins (version 2.32.3)
In the configuration of the job, I specified a check out into a subdirectory: Open the configuration, e.g. https://myJenkins/job/my-job/configure. At the bottom, see section Pipeline -> Additional Behaviours -> Check out into a sub-directory with Local subdirectory for repo set to, e.g., my-sub-dir.
Expectation: Upon check out, the Jenkinsfile ends up in my-sub-dir/Jenkinsfile.
Via the option Script path, you configure the location of the Jenkinsfile so that Jenkins can start the build. I put my-sub-dir/Jenkinsfile as value.
I then received the exception you pasted in your question. I fixed it by setting Script Path to Jenkinsfile. If you don't specify a sub-directory for check out, then still try double checking values for Script Path.
Note: I have another Jenkins instance at work. There I have to specify Script Path including the custom check out sub-directory (as mentioned in Expectation above).
GO TO Job-->Config-->Pipline and uncheck checkbox lightweight checkout"
lightweight checkout : selected, try to obtain the Pipeline script contents >directly from
the SCM without performing a full checkout. The advantage of this mode
is its efficiency; however, you will not get any changelogs or polling
based on the SCM. (If you use checkout scm during the build, this will
populate the changelog and initialize polling.) Also build parameters
will not be substituted into SCM configuration in this mode. Only
selected SCM plugins support this mode.

Jenkins Shared Libraries context

I have a pipeline job which loads Jenkinsfile from git repository. My Jenkinsfile looks like this:
#!groovy
#Library('global-utils-lib') _
node("mvn") {
stage('build') {
checkout scm
}
stage('merge-request'){
mergeRequest()
}
}
global-utils-lib is shared library loaded in Global Pipeline Libraries from another git repo with following structure
vars/mergeRequest.groovy
mergeRequest.groovy:
def call() {
sh "ip addr"
def workspacePath = env.WORKSPACE
new File(workspacePath + "/file.txt").text
}
Job is run against docker container (docker plugin).
When I run this job then docker container is provisioned correctly and scm is downloaded but I get FileNotFoundException.
It looks like code from shared library is executed against jenkins master not slave:
presented IP comes from master
file is loaded correctly when I pass correct path to the scm on master
How can I run library code against slave? What I am missing?
It's generally not a good idea to try and do things like new File() instead of using existing Pipeline steps.
Your Pipeline script is interpreted and executed by the Jenkins master so, as you're seeing, the attempt to use the File API doesn't work as you might expect.
Sticking to Pipeline steps helps ensure that your pipeline is durable (i.e. survives restarts), is pausable, and doesn't block the execution thread, preventing parallel steps from working, for example.
In this case, the existing readFile step can be used.
I don't know how well the Docker Plugin interacts with Pipeline (though I imagine it should be transparent), and without knowing which agents have the "mvn" label, or whether you can reproduce this outside of a shared library, it's unclear why your sh step would appear to be running on the master.
The Docker Pipeline Plugin is explicitly designed for Pipeline, so it might give better results.

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