How to delete offline (agents/nodes) from Jenkins in SWARM mode

Question

How do I delete a node from Jenkins? Jenkins operates in Docker Swarm mode.

When I am trying to remove the offline container, swarm keeps generating new containers

Answer 1

You can try:

Using Jenkins Pipeline:

node("master") {
println "Cleaning up offline slaves..."
    hudson.model.Hudson.instance.slaves.each {
      if(it.getComputer().isOffline()) {
        println "Deleting ${it.name}"
        it.getComputer().doDoDelete()
      }
    }
    println "Done."
}

Using SH

#!/bin/bash

# This script should be run on the Jenkins master. We set up a job in Jenkins to run this once a week on master.

function jenkins-cli {
  java -jar /var/cache/jenkins/war/WEB-INF/jenkins-cli.jar -s http://localhost:8080 "$@"
}

for slave in slavename1 slavename2 slavename3; do
  if [[ `curl -s "http://localhost:8080/computer/${slave}/api/xml?xpath=*/offline/text()"` = "true" ]]; then
    echo "$slave is already offline. Skipping cleanup"
  else
    echo "Cleaning up docker on $slave"
    echo "Taking $slave offline"
    jenkins-cli offline-node $slave -m "Scheduled docker cleanup is running" && \
      echo "Waiting on $slave to go offline" && \
      jenkins-cli wait-node-offline $slave && \
      while [[ `curl -s "http://localhost:8080/computer/${slave}/api/xml?xpath=*/idle/text()"` != "true" ]]; do echo "Waiting on $slave to be idle" && sleep 5; done && \
      echo "Running cleanup_docker on $slave" && \
      ssh -o "StrictHostKeyChecking no" $slave -i /var/lib/jenkins/.ssh/id_rsa "sudo /usr/local/bin/cleanup_docker"
    echo "Bringing $slave back online"
    jenkins-cli online-node $slave
  fi