Alexandru Bantiuc's answer worked well for me to stop the build, but my executors were still showing up as busy. I was able clear the busy executor status using the following
server_name_pattern = /your-servers-[1-5]/
jenkins.model.Jenkins.instance.getComputers().each { computer ->
if (computer.getName().find(server_name_pattern)) {
println computer.getName()
execList = computer.getExecutors()
for( exec in execList ) {
busyState = exec.isBusy() ? ' busy' : ' idle'
println '--' + exec.getDisplayName() + busyState
if (exec.isBusy()) {
exec.interrupt()
}
}
}
}