Eucalyptus Systems, the open source private and hybrid cloud merchant that just tied up with Amazon, has gotten a $30 million C round on top of the $25.5 million it's already gotten. It says the C round was oversubscribed.

The funding was led by Institutional Venture Partners (IVP). Existing investors, including Benchmark Capital, BV Capital and New Enterprise Associates (NEA) pitched in too.

Eucalyptus claims to be the most widely deployed on-premise IaaS cloud platform, but, according to Marten Mickos, who runs the joint, at $55.5 million, Eucalyptus is the "least funded" of the current crop of players like VMware, OpenStack and now CloudStack, which have got hundreds of millions of dollars at their disposal.

It doesn't have a sugar daddy or big corporate interests it has to kowtow to either, he mused, so its development team can be focused and make "consistent, principled, uncomfortable choices." It also doesn't have to worry about fragmentation. And although it doesn't have a big community or big customer base it has hopes.

"Q4 was amazing," he said. "Then we delivered Eucalyptus 3.0 and signed the Amazon deal." At that point things apparently began to heat up. Now it's got more money to throw at it and expand operations, very different from a year ago when the press was getting ready to write Eucalyptus' epitaph.

Besides Amazon, which will now countenance folks migrating workloads between Eucalyptus private clouds and Amazon's great big propriety public cloud because they share APIs, the start-up's got similar deals with Wipro Infotech in India and CETC32 for its Hua-Cloud offering in China. Its partner ecosystem has more than doubled to include over 200 of the top cloud and infrastructure automation vendors. And it says it's now enabling 25,000 cloud starts a year.

Customers include Sony, Aerospace Corporation, InterContinental Hotels Group, the USDA and Puma.

Eucalyptus says it's nearly tripled staff in the last year-and-a-half and is continuing to hire across-the-board.

IVP gets a board seat. It'll go to general partner Steve Harrick.

Mickos is the guy who sold the open source MySQL database to Sun for an absurd $1 billion. IVP made a similar late-stage investment in MySQL.