Canonical has stated that its Ubuntu Server needs increased support from independent software vendors and system builders.

"The acid test for Ubuntu Server is Oracle," Canonical chief executive Mark Shuttleworth told vnunet.com in an interview at the VMworld 2007 conference in San Francisco.

Ubuntu is best known for its desktop Linux distribution which Dell ships on its consumer Linux desktop PCs, but the group is seeing increasing interest in its server version that was launched in 2005.

Certification for third-party applications such as Oracle's database is considered critical for the continued growth of Canonical's support services.

Firms that seek professional support typically also require that their software and hardware are certified to run the Linux distribution.

Ubuntu Server is different from Red Hat and Novell because the software is not sold as a subscription with support. Support is available from Canonical, the project's corporate sponsor.

Increased vendor support could boost Ubuntu's overall credibility. Oracle's support for Linux in 1998 is considered a watershed moment in the history of the open source operating system.

As Oracle's database is the most widely used mission-critical enterprise application available, its support instilled a new level of trust in Linux.

But the enterprise software giant might not be as eager to throw its weight behind Ubuntu.

Oracle launched its Unbreakable Linux initiative last year, which is essentially a special Oracle distribution of the open source operating system. This renders Ubuntu a potential competitive threat.

Oracle might not be able to hold out for long, however. Although Shuttleworth typified adoption rates as being at an "early stage", he claimed that the software is penetrating deeper into the enterprise.

Enterprise adoption of Ubuntu Server is following a pattern typical to open source software. Technology enthusiasts start experimenting at home, then deploy it on non-mission critical systems such as file and print servers.

Ubuntu Server is currently starting to move up the chain in areas such as high performance computing, but the final missing piece is support from hardware vendors.

Sun Microsystems is currently the only major system builder which certifies its hardware for Ubuntu.

But Shuttleworth argued that Ubuntu can put firms in touch with the open source community. Red Hat and Novell, in comparison, position themselves as a platform provider offering a one-stop shop.

"We have to leverage our insight into how open source really works," said Shuttleworth. "We do not see ourselves as the sole platform provider. We are leaner [than Red Hat or Novell]."