Canonical has agreed to offer Ubuntu server operating support to Zentyal customers. The result: Zentyal and its authorized server partners can more easily engage small and midsize (SMB) customers, the company claims. Admittedly, Zentyal isn’t a household name in the United States, but the Canonical-Zentyal agreement sheds more light on Canonical’s international growth strategy for Ubuntu channel partners.

On the one hand, Canonical increasingly positions Ubuntu, a Linux distribution, for public and private cloud computing. But on the other hand, Canonical continues to invest in Ubuntu’s mobile, desktop and small business server capabilities.

Zentyal, meanwhile, specializes in Linux small business servers. From its headquarters in Spain, the company has been making noise across Europe. But Zentyal has larger aspirations: The Canonical-Zentyal agreement is a worldwide, multi-year engagement.

For its part, Ubuntu seems to be gaining more and more international momentum. In addition to the Zentyal deal, Dell this week announced plans to offer Ubuntu preloaded on PCs in India. Dell also works closely with Canonical on cloud computing initiatives.

Still, Ubuntu’s momentum as a desktop and mobile operating system in the United States seems unclear. Around 2008, netbooks and some PCs preloaded with Ubuntu popped up in U.S. retail stores and on some major PC vendor websites. More recently, Ubuntu-based PCs have been more difficult to find in North America — though boutique PC makers like ZaReason and System76 continue to promote Ubuntu-based systems.

Also of note: The small business server market as a whole seems to be slowing down as customers increasingly shift applications to the cloud. One example: The VAR Guy doesn’t hear much buzz about Microsoft Small Business Server and rival offerings anymore.