IBM plunged its proprietary mainframes headlong into the open source waters, delivering two Linux-only mainframes and its largest mainframe code drop to the open source community.

IBM also signed an agreement with Canonical Ltd. to create a version of Ubuntu for IBM's z Systems and committed to enable products, such as Apache Spark and MongoDB, on z Systems.

Hoping to attract cost-conscious users to the new Linux mainframes, called LinuxONE, IBM is offering a subscription-based, pay-as-you-go pricing model for both the hardware and software. The new pricing model sidesteps the steep, upfront costs typically associated with mainframes, according to the company.

This dive into the open source market is largely inspired by the explosive proliferation of transactions from mobile devices, as well as the increasing workloads driven by social media, according to IBM officials.

"We are going all in, because users tell us about the digital disruption they are going through," said Ross Mauri, general manager of IBM's z Systems. "The transactions kicked off by mobile hitting [mainframe systems] are growing exponentially. Their desire to do analytics closer to operational data and increasing cloud deployments are the other reasons."

Some longtime mainframe veterans like the aggressive move on IBM's part, as open source has become an economic necessity.

"We like the trend we see with companies like IBM mixing open source with proprietary [products], because it's what we have to do to get a handle of costs," said one IT professional with a large Minneapolis-based manufacturing company. "Training and support can be a problem in trying to get everything to work together, but we just have to work through that. We'll take the tradeoff."

The higher-end of the two mainframes, LinuxONE Emperor, is based on IBM's z13 mainframe and designed to analyze transactions in real time. It can be scaled to handle up to 8,000 virtual machines and thousands of containers, company officials said. The lower-end system, LinuxONE Rockhopper, is intended for mid-sized companies or companies in emerging markets.

IBM's Linux friendship goes way back IBM first waded into Linux on mainframes in 2001, and has slowly but steadily convinced some corporate users to make the switch from its proprietary z/OS mainframe operating system. About one-third of IBM's mainframe users run Linux, with 27% of the installed mainframe capacity running Linux, according to Mauri. Some users running Linux on Intel-based systems over the past several years said they will take a look at the new mainframes, particularly the lower-end Rockhopper, as a possible way to consolidate and better manage dozens of their departmental servers flung across the enterprise. "As we grow [our server base] out across the country, we have some difficulty in managing and tracking the activities on them," said a purchasing agent with a large transportation company in Jacksonville, Fla. "The security with these things looks pretty interesting." IBM officials said both LinuxONE systems have IBM's protected key, a technology they claim offers significantly better security compared with clear-key technology. The agreement with Canonical to create a version of Ubuntu specifically tailored for the new mainframe systems aims to bring some of the scale-out and cloud capabilities of that operating system to bear. The deal does not impact the existing agreements IBM has in place with Red Hat Inc. and SUSE, whose respective versions of Linux are also available on IBM mainframes, IBM officials said. "This should help users put new workloads in the right place and for the right purpose," said John Zannos, Canonical's vice president in charge of alliances. "You will see more of this from us over the next year that will be quite disruptive." One CIO agrees with Zannos' assertion. "IBM believes by supporting these new areas, they can garner new sales, as people scale up the work they are doing in open source," said Nigel Fortlage, vice president of information technology and CIO of social business for GHY International, a provider of integrated services for customs brokerage and customs consulting in Winnipeg, Canada. Support from major players in the open source community bodes well for IBM's credibility in developing this space, Fortlage added. Besides Apache Spark and MongoDB, IBM said it will better enable other well- known open source software for the new systems, including Node.js, MariaDB, PostgreSQL and Chef. SUSE, which provides a Linux distribution for the mainframe, said it will now support kernel-based virtual machines (KVM), which it believes gives users another viable hypervisor option. Fortlage, whose shop runs IBM Power servers on Linux, said the new Linux mainframes support the same open source operating systems, as well as many of the same applications and tools as the Power series, which could offer corporate users a cleaner upgrade path. "To have a common environment that crosses all of their key server platforms should allow users to move workloads onto whatever platform can best handle the work," Fortlage said. "It's a straightforward path to scalability."