Build Your Own Cloud with Eucalyptus

In the March 2010 issue, I wrote an article on how you could deploy Ubuntu 9.10 as part of Amazon's EC2 cloud computing service. Amazon's EC2 service can be useful, but what if you have a bunch of machines already and don't want your data outside your network? Or, what if you don't want to pay the ten-cents-per-hour fee that Amazon charges? That's where the Ubuntu Enterprise Cloud comes in. The Ubuntu Enterprise Cloud system ships with the Server Edition of Ubuntu 9.10, and it's based on the Eucalyptus cloud cluster software.

What exactly is Eucalyptus? Put simply, Eucalyptus is an open-source, Amazon EC2-compatible, cloud computing cluster package that can be run on commodity Linux machines. Although VMware and VirtualBox do similar things, Eucalyptus allows you to scale your cluster across multiple machines. When you run out of resources to run another VM, you simply can pop a new Eucalyptus server on your network, and you're off and running.

Now that you're all fired up, let's get started with the Ubuntu Enterprise Cloud (UEC). The easiest way to get started with UEC is to do a fresh installation of Ubuntu 9.10 Server with the UEC option. You need two systems at a minimum to build your first cloud. One will be the cloud controller (the master node that dispatches and monitors the instances of the virtual machines), and the other will be the node controller (where all the instances actually will run). Minimum configurations are listed in the installation documentation (see Resources), but I recommend a dual-core, 2GHz machine with 2GB of RAM and a 100GB disk as a realistic usable minimum for each. Note that you will need Virtualization Extensions (VT) enabled on the node controller machine. Eucalyptus requires that. Your systems can be either 32-bit or 64-bit (mine are both 64-bit), but be advised that although the 64-bit host can run a 32-bit instance, the opposite is not true.

First, let's install the cloud controller. To start the install, boot your machine off an Ubuntu 9.10 Server CD, select Install Ubuntu Enterprise Cloud at the boot menu, and then press Enter. That starts the standard text-based install, with a twist: along the way, you'll be asked what type of cloud installation mode you want—a “Cluster” or a “Node”. Because you're installing the cloud controller first, select Cluster and press Enter. The installer will proceed normally, but it will ask you two more questions unique to the Ubuntu Enterprise Cloud installation: the name of your cluster (this is just a unique identifier like “testcluster”) and a range of IP addresses on your LAN that the cloud controller can allocate to instances. Once you've done that, the installer will finish out much like a regular Ubuntu text-based install, and your machine will reboot. That's it! Your cloud controller is now on-line.

Next, you need to install a node controller. This is even easier. Boot the computer that will become the node controller from the same Ubuntu 9.10 Server CD, select Install Ubuntu Enterprise Cloud from the boot menu, and the installer should detect the cluster automatically and select Node within the installer. Simply press Enter to confirm you want to install a node and confirm your system's partitioning scheme, and the rest of the installation is completed for you. The installer even copies your login account over from the cloud controller.

Now that your nodes are up, you need to register the node controller with the cloud controller. Log in to the cloud controller, and run the command:

sudo euca_conf --no-rsync --discover-nodes

The cloud controller will auto-discover the nodes that are running the node controller service, and it will prompt you to register each by its IP address.

Before you can use the cloud, you've got to register yourself with it and obtain credentials. Fire up a Web browser (either on the cloud controller or on another machine on the LAN), and go to this URL: https://<cloud-controller-ip-address>:8443. You have to use a secure connection, and you'll get a security certificate warning from your browser. Once you accept the cert warning, use the user name “admin” and password “admin” to log in to the page (Figure 1). Then, you'll be prompted to change the admin password and fill in your e-mail address, so the UEC can mail you information about your instances.

Figure 1. The Ubuntu Enterprise Cloud Login Page

Next, you need to get your credentials to a location where you can use them. I prefer to do this on the cloud controller, so run this script as your regular user on the cloud controller:

mkdir -p ~/.euca
chmod 700 ~/.euca
cd ~/.euca
sudo euca_conf --get-credentials mycreds.zip
unzip mycreds.zip
cd -

This drops your credentials for the UEC into the ~/.euca directory. The credentials can be downloaded from the UEC admin portal to another Ubuntu machine for use if you so desire. Next, you need to add the line . ~/.euca/eucarc to your shell's profile (~/.bashrc on an Ubuntu machine or the cloud controller) to source the eucarc file every time your shell starts. If you're on another machine aside from the cloud controller, you need to install the euca2ools package as well.

Now that the prep work is done, you can verify that the cluster is working properly by running the euca-describe-availability-zones verbose command:

bill@falcon:~$ euca-describe-availability-zones verbose
AVAILABILITYZONE     cluster1        192.168.1.116
AVAILABILITYZONE     |- vm types     free / max   cpu   ram  disk
AVAILABILITYZONE     |- m1.small     0002 / 0002   1    128     2
AVAILABILITYZONE     |- c1.medium    0002 / 0002   1    256     5
AVAILABILITYZONE     |- m1.large     0001 / 0001   2    512    10
AVAILABILITYZONE     |- m1.xlarge    0001 / 0001   2   1024    20
AVAILABILITYZONE     |- c1.xlarge    0000 / 0000   4   2048    20