You have to deploy a small software agent on your server for ScaleXtreme to manage it. The agent is very small (for Windows it is roughly 7MB and for Linux 3MB), and takes up almost no system resources when you are not doing anything with it on the server. You can read more about how the agent communicates with the cloud and what it does on our Architecture & Security page. The ScaleXtreme agent is natively compiled for the platform to remove any dependencies on any additional software (such as requiring Java or other packages to be installed).
We have broad support for almost all Windows and Linux platforms, for both 32 and 64 bit editions. The agent software download is available within the product (as the software agent is custom generated for each account), so once you create your account you will find a link to download and deploy the software. The agent software is fully tested on machines that run on public cloud providers (such as Amazon EC2 and Rackspace) and virtualized platforms (such as VMware). We have built some auto-deployment wizards for certain cloud providers to make it really easy for you to deploy the software on all your existing servers.