Monthly Archives: July 2009

Consistent Development Environments using VirtualMachines

As a development team we always run into situations where we have trouble setting up a proper development environment for each of the team members to get going or add new staff on the go. It annoyed me every time since it causes a lot of unnecessary communication and friction.

I often heard of virtualization but never actually played seriously with it. The idea is:

If we could have a virtual machine for every project that contains an equivalent environment like the production system, everybody working on it…

  • … could just rely on his development environment by just starting the VM without having to set up anything half-baked themselves.
  • … could use his favourite working environment OS, IDE and tools on which they are most comfortable and thus happy and productive.
  • … could work on their own checked out working copy using version control.
  • … could immedately see what they built refreshing the local browser or starting Unittests on the VM via ssh to check their dev increments.

We used A good starting point to get to know VirtualBox better and learn how to start your first virtual machine:

Our target was to be able to startup the development VM as guest system on any developers development machine being the host system, open a browser on the host (!) and call for example http://develop/ to see the webroot of the VM. Additionally we set up samba and ssh on the VM in order to have the webserver’s webroot on the VM available via the filesystem. In order to do that you need to…

  • …start your VM with networking set to ‘Host interface’ instead of the default NAT. This is explained in detail on this page (sorry German) – for me it was tricky to get the guest machine available on the host and have internet access at the same time.
  • …edit the hosts file (on OSX ‘sudo nano /private/etc/hosts’ and reboot) on the development machines and add something like the following line: ’ develop’. To find out the IP enter ‘sudo ifconfig’ (OSX/Linux) on your host system after you have started the VM. You will see aditional adapters set by virtualbox and the IP address.
  • …configure /etc/samba/smb.conf on the VM, restart samba and connect (e.g. smb://develop/webroot). We check out a working copy of the applicaton under development directly onto the webroot and create a new PHP-Project there in our IDE. Update and commit directly from there.

If you search the web for ready-made VMs you find mostly VMware images. You can not run them directly in VirtualBox and need to convert them.

Under Linux you can convert the VMware image (.vmdk) into a VirtualBox image (.vdi) like this:

sudo apt-get install virtualbox-ose virtualbox-ose-guest-utils;
sudo apt-get install qemu;

qemu-img convert xxx.vmdk xxx.bin;
VBoxManage convertdd xxx.bin xxx.vdi

Install the required packages with apt-get install once. VBoxManage is part of VirtualBox. The last two lines do the conversion.

We ended up creating a fresh install from a Debian 5 netinstall iso. The iso-file can be mounted as CDROM on the creation of the new VM with VirtualBox. Receipes for setting up the appropriate LAMP environment with apt-get install can be found on the web. You only have to do it once. Save the state of your VM afterwards.

There are ways to generate a virtual machine from a physical server. Use Google to find receipes. I used on a Debian Etch system with the live CDROM from This requires that you are able to umount your filesystem or rather boot into the live cd on the production/staging machine in order to generate the partimage.

You mount an external drive over the network or a usb harddrive. The partition (e.g. /dev/sda1) you would like to backup must be umounted. From the live cd you can see your partitions, including attached usb drives, with the ‘fdisk -l‘ command. Just mount the target (e.g. /mnt/usbdrive) and start partimage from the commandline. Dialogues guide you through the image creation.

In case you wonder what is meant by the ‘Host key’ to enter or leave a running VM with your mouse… it is the right (!) Strg-Button on your Keyboard.

I just installed Ubuntu Server on a VM from my MacBook. To have a usable keyboard once you logged on to the new VM, you must do the following in order to have a keymap including the pipe symbol, braces etc.:

  • sudo apt-get install console-data; #to install the keymaps
  • sudo loadkeys mac-macbook-de; #to set the keymap for German MacBook

Once you have done that, you can use your right Command-Key as ‘Alt-Gr-Key’ like on a PC keyboard. The pipe symbol is then typable with ‘Alt-Gr + >’, Braces and Brackets are typable via ‘Alt-Gr + 6,7,8,9′.

This is how you copy a virtual machine using VirtualBox tools:

$ VBoxManage clonevdi /Users/marco/MyMachine.vdi /Users/marco/MyMachine_copy.vdi
$ VBoxManage internalcommands setvdiuuid /Users/marco/MyMachine_copy.vdi