Example of running a command on all slaves

run-on-all-slaves-example.groovy

import hudson.util.RemotingDiagnostics

Jenkins.instance.slaves
  .findAll { node -> node.labelString.contains('debian') } // not production-safe
  .each { slave ->
    println slave.name
    
    def channel = slave.channel
    if (channel != null) {
      println RemotingDiagnostics.executeGroovy("""
        def p = 'docker --version'.execute()
        p.waitFor()
        println p.in.text.trim()
      """, channel)
    } else {
      println 'host is down'
      println ''
    }
  } 

Thank you. Very helpful.