The companies ramp up their existing interoperability deal that gives corporate users a bridge between Windows and Linux.
Microsoft on Wednesday extended its existing partnership with Novell with a pledge to pump up to an additional $100 million into the deal.
The companies, which announced an interoperability deal two years ago, said that Microsoft will purchase up to $100 million in certificates that its customers can redeem for Novell's Suse Linux service and support.
The new Microsoft investment will begin in November, the companies said.
The deal is centered on interoperability between Windows Server and Suse Linux Enterprise Server. The original deal, a five-year interoperability partnership inked in November 2006, called for Microsoft to buy $240 million worth of such certificates. Novell said that it has already invoiced more than $157 million in certificate revenue in 18 months.
The companies said that between now and November, they "will solicit customer input and identify aspects of the support programs that will be most useful to organizations running mixed-source environments."
The initial deal between the companies was roundly criticized by open-source advocates as conflicting with licensing provisions. Corporate customers, faced with the realities of making mixed-operating system environments work, have welcomed the deal. Microsoft and Novell said that customers taking advantage of the partnership include BMW, HSBC Holdings, Southwest Airlines, and Wal-Mart.