Some analysts question whether those strategic features will over time become propriety features that would curtail the whole point of having an open source-based stack: being able to avoid vendor lock-in because writing a cloud application to an open standard is supposed to provide some portability options.
"The race is basically over unless the vendors who are building their private cloud offerings on OpenStack decide to get greedy and built proprietary features that could give them an appealing edge in that market, but could also lead to some levels of OpenStack interoperability issues down the road," Enterprise Management Associates analyst Torsten Volk says.
Gartner's Lakhani says portability is a distant prospect for most enterprises looking to build a private cloud today. He argues it is going to be at least 12 to 18 months before private cloud users are going to really demand that they be able to run applications across OpenStack platforms.
Volk did point to the OpenStack Foundation's efforts to ramp up platform certification efforts to help preclude any issues that might lead to users getting locked into one OpenStack platform or another due to application dependencies.Industry watchers say Eucalyptus's strength and its weakness are its ties to Amazon. The company which brags of tens of thousands of downloads of its Amazon-compatible cloud software and $55.5 million in venture capital money (including $30 million picked up last year) -- says it offers API parity with 90% of the popular services offered by AWS including EC2, S3, EBS, IAM, Autoscaling ELB and CloudWatch. So an application running on a Eucalyptus private cloud using its AWS compatible services could burst out into the Amazon cloud using those same services.
"When a customer puts in one of our clouds, they become an instant member of the Amazon ecosystem," says Eucalyptus CEO Marten Mickos.
Forrester's Nelson lauds Eucalyptus for having a very complete technology offering that is much more readily consumable when compared to OpenStack. That does translate to a strong hybrid cloud proposition, which many enterprises are considering.
"But on the other hand you've got Amazon continuously downplaying the need for private cloud, so that might not bode well for Eucalyptus' plans," Nelson says.
The Apache CloudStack offering also has strong ties to Amazon public clouds in that it offers an API translator so that applications written for CloudStack can also run in AWS.
And Citrix's Ulander argues that its success with larger deployments which admittedly tend to be mostly service provider installations "shows that our stack has gone beyond the typical greenfield and dev/test deployments and into supporting revenue-generating applications."
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