A coalition of equipment providers have joined to develop a new specification for controlling servers over the network, promising to eliminate data center vendor lock-in.
The new spec, Redfish, supports out-of-band management, a vital operation for data centers because it provides a way to control machines even when the operating system is not installed or functional, or if the machine itself is not powered on.
Redfish aims to replace a widely used out-of-band specification developed in 1998, the Intelligent Platform Management Interface (IPMI). IPMI is no longer interoperable across different brands of servers, and is straining to meet the requirements of today’s massive multiscale environments.
“Companies like Facebook have these big scale-out data centers, and that is a very hard market to address right now,” said Peter Kueth, product marketing manager for Emerson Network Power, an Emerson business division that specializes in IT infrastructure equipment.
Server vendors Dell and HP—or the part of HP soon to be recast as Hewlett-Packard Enterprise—as well as chip manufacturer Intel and Emerson Network Power created the first draft of the specification. The IT standards body Distributed Management Task Force (DMTF) is expected this week to adopt the specification as a standard and create a working group for its final development.
With Redfish under DMTF stewardship, more users may feel comfortable that the specification is a true open standard not controlled by a small number of parties, Kueth said.
On the server, out-of-band management is handled by a baseboard management controller, a card that operates independently of the server software itself. Emerson is one of the largest providers of baseboard management controllers.
The Redfish specification prescribes a set of commands that a server’s baseboard management controller should respond to, so data center operators can control different aspects of a server’s operation from across the network.
Compared to IPMI, Redfish provides a richer set of information, which should be more easily interpreted by scripts and administrator programs. “Because it is human readable, programmers who do not have expertise in this field can now write software to have their server do what they need it to,” Kueth said.
Redfish also takes advantage of today’s more memory-rich baseboard management controllers by adding in more security features, such as support for secure HTTP communications. Redfish communications should also be faster in that they can be executed in parallel, in contrast to IPMI’s communications protocols, which must be executed one-at-a-time, in serial.
Another drawback with IPMI is that it has splintered into a number of different, incompatible implementations.
HP offers ILO and Dell offers DRAC, for instance.
As a result of these incompatible variants, data center managers who wish to streamline remote operations are confined to using only one vendor’s server.
“If you are ILO shop, you probably more likely to buy an HP server, because you already have HP’s server system software to talk to all of these servers,” Kueth said.
Redfish is designed to be extensible, so vendors can extend the standard to support their own features, without breaking compatibility with Redfish’s basic core of services. “If I extend it, it doesn’t break reverse compatibility,” Kueth said.
Beyond servers, Redfish could also be used to control network switches, power distribution systems, storage servers, and other network connected devices.
“Redfish is basically a schema, a dataset and a transport based on commonly used Web services,” so it can be used within a large set of computational networked devices, Kueth said.
At this time, Redfish is not backward-compatible with IPMI, though Kueth expects that the first few generations of servers that will run Redfish will also run IPMI, so that users can plan to migrate their servers to the new specification over time.
Kueth acknowledged that the specification is in part a response to the Open Compute Project, a Facebook-led initiative to create a set of open standards for data center hardware independent of hardware manufacturers and eliminate vendor lock-in.
Open Compute is also looking at standardizing remote server control, though has not yet joined the Redfish effort.
“Open Compute’s manageability goals is very similar to the goals of Redfish, but they are not the same effort,” Kueth said.