The Linux services will go live on Azure at 4 a.m. EDT on Thursday. At that time, the Azure portal will offer a number of Linux distributions, including Suse Linux Enterprise Server 11 SP2, OpenSuse 12.01, CentOS 6.2 and Canonical Ubuntu 12.04. Azure users will be able to choose and deploy a Linux distribution from the Microsoft Windows Azure Image Gallery and be charged on an hourly pay-as-you-go basis.

In Suse's case, Azure users will be able to provision the latest edition of either the Suse Linux Enterprise Server or OpenSuse. "To set up an instance, they just pick the Suse enterprise image and provision it like they would on any other cloud service," said Doug Jarvis, Suse product marketing manager for Cloud. Suse can automatically update these virtual distributions with security patches, bug fixes and new features.

Azure users will also deploy applications they've built with the Suse Studio IDE (integrated developer environment) directly onto Azure. In this case, they do not need to worry about the machine image. Instead, they will enter their Azure ID into Suse Studio before deploying their application to the Azure cloud.

The move may be a surprising one for observers of Microsoft, which has traditionally considered itself a platform company, built around the enormous success of Windows. As such, the company has traditionally seen Linux as a , especially in the server market, where it competes with Windows Server for replacing traditional Unix servers.

With its Azure cloud service, however, Microsoft faces a formable rival in the popular Amazon Web Services -- which such as Canonical Ubuntu and Red Hat Enterprise Linux in addition to Windows.