Author: Jon Hass
As revealed in a joint press release yesterday, Dell is participating in a coalition including Emerson, Hewlett Packard, and Intel whose purpose is to create a new industry standard for the management of data center hardware. The initial Redfish specification, which specifically targets server management, will be publically available once published by an industry standards body such as Distributed Management Task Force (DMTF). But today, I want to talk a little about this standard and what it might mean for Dell customers.
Dell has a long history of supporting industry standards, from IPMI, which was introduced in 1998, to more recent standards such as SMASH. Five years ago, Dell introduced its web services interface (WSMAN) and has since evolved it into one of the world’s most sophisticated and capable server management APIs. Backed by this kind of experience, Dell is a critical partner in the Redfish project, and our participation continues this long legacy of supporting industry standards.
As with previous industry standards, Dell’s support is a boon to our customers, allowing them to limit the number of management processes needed to manage a multitude of servers. Redfish is no different in this respect, but it brings much more to the table. With scale-out data centers becoming more and more common, a standard that can comprehend the vicissitudes of today’s complex environments is needed.
Leveraging existing web protocols such as JSON and HTTPS while embracing RESTful design principles and a light weight data model, Redfish is built to meet the challenges of today’s large scale data centers who primarily manage to the lowest common denominator: IPMI.Though IPMI has served the industry well, it was designed for an earlier era of computing, falling short in describing today’s complex, and more and more disaggregated, computer systems. Several computer security researchers, such as Dan Farmer, have pointed to vulnerabilities with many implementations of IPMI. For this reason, Redfish is designed from the ground up with security best practices in mind.
Another advantage to Redfish is that it is opaque, meaning that, unlike IPMI, it does not prescribe the implementation to server vendors like Dell. Instead, it is limited to the API only. Furthermore, the protocol and data model can be revised independently, which will reduce the complexity of implementing any future revisions.
So, what can Redfish do? Though Redfish will evolve, the initial specification defines a set of management capabilities similar to those available in IPMI:
Retrieve Telemetry- Basic server identification and asset information- Health state- Temperature sensors and fans- Power consumption and thresholds
Discovery- Service endpoint (network-based discovery)- System topology (rack, chassis, server, node)
Basic I/O Infrastructure Data- Host NIC MAC addresses for LOM devices- Simple hard drive status / fault reporting
Security- Session-based leveraging HTTPS
Common Management Actions- Reboot / power cycle- Change boot order- Configure BMC network settings- Manage user accounts
Access and Notification- Serial console access via SSH- Alert / event notification- Event log access
Since the joint announcement of Redfish, several questions have been raised about what this means for the future of IPMI and Dell’s WSMAN interfaces. To be clear, Redfish, once it is broadly implemented, will be ideal for large heterogeneous data centers, but at the moment, it currently offers a fraction of the capability in Dell’s WSMAN interface.
For this reason, Dell still recommends WSMAN as its primary application programming interface and will continue to invest in it for the foreseeable future. Until Redfish is implemented in a large amount of industry server hardware, IPMI will still be a critical standard in the data center. Therefore, until this happens, Dell has no plans to drop support for IPMI in its server products.
To learn more about Redfish, please visit www.redfishspecification.org.