How can Jenkins autostart a VirtualBox slave?

Question

I have a VirtualBox Jenkins slave. I start it manually every time it goes down (e.g. after doing reboot to the PC).

Is there a way to make Jenkins start it automatically?

Answer 1

I have a Windows host that should run an Ubuntu 14.04 virtual machine Jenkins slave.

Pre-requirements: you should have a VM slave defined in Jenkins (http://YOUR-JENKINS-URL/computer/)

This is how I solved it:

1) Setup Ubuntu VM to automatically start a service on boot that runs a script to start Jenkins slave:

• Use upstart to run the script: create a the file /etc/init/jenkins-slave.conf

  description "A job to start a Jenkins slave"
  author "Your Name"
  start on runlevel [2345]
  exec echo Starting Jenkins slave at `date` >> /var/log/jenkins-slave-job.log
  exec /jenkins/run.sh
  

• The /jenkins/run.sh:

  cd $(dirname $0)
  java -jar slave.jar -jnlpUrl         
  http://YOUR-JENKINS-URL/computer/NAME-OF-NODE/slave-agent.jnlp -secret 51d080f68b3d2552c977840aa8a01bb371a1b3e8b3326f36fadb497e597185ce
  

• The /Jenkins folder should contain slave.jar file downloaded from Jenkins node page.

• The 2 last lines in the run.sh file should be taken from the Jenkins node page.

2) Setup Windows to start the VM on startup:

• Create a Windows shourtcut with the following value in the "Target:"

  "C:\Program Files\Oracle\VirtualBox\VBoxManage.exe" startvm "UbuntuVBox"
  

• Where UbuntuVBox should be replaced with the name of your VM

• Put the shortcut under "Startup" folder in the Windows start menu

To conclude:

After doing the above steps - if you reboot the Windows host, it should run the shortcut, that will run the VM. The VM will run the service "Jenkins-slave" and your Jenkins slave should be up and running.

Answer 2

Short answer:

Yes, we can do it.

Just add VitrualBox as a service in your PC, and add Jenkins Slave as an service in that VitrualBox VM.

Long answer:

In fact, we are talking about two things here:

1. how to auto-start a VirtualBox VM when the host of VirtualBox is restarted.
2. how to auto-start a jenkins slave when this node client is restarted.

Or , in another word , we are talking one thing:

3. how to auto-start some stuff when computer restarted.

But the detail operations related to the OS you are using. (For windows, this tool may help: https://nssm.cc/)

Answer 3

There is a VirtualBox Plugin that:

• starts VMs automatically when needed

• stops VMs when no longer needed

It requires VirtualBox web service (vboxwebsrv) to control VMs (see e.g. chapter 9.12 of the VirtualBox documentation to get it running).