By Ann Silverthorn
At last month’s Storage Networking World (SNW) conference, the Storage Networking Industry Association announced new specifications that recently passed SNIA approval for further development, including the iSCSI Management API, Multipath Management API, and Common RAID Disk Data Format (DDF). The SNIA also provided road-map updates for the Storage Management Initiative Specification (SMI-S).
SMI-S v1.1, released last month, has been expanded to include management services (including data protection) for all components in a heterogeneous storage environment. SMI-S 1.1 also addresses NAS and iSCSI arrays, storage media libraries (SMLs), and host-discovered resources (HDRs). SMI-S v1.0, which was released in March 2004, focused mainly on asset management and auto discovery (SAN arrays, fabrics, switches, and host adapters).
By April 2006, the SNIA plans to release SMI-S v1.2, which will be “application-aware,” allowing data to be moved wherever needed based on storage-centric data life-cycle management tools.
IMA, MMA, and RAID DDF
The SNIA’s iSCSI Management API (IMA) was expected to be approved this month and will enable multi-vendor iSCSI management independent of iSCSI host bus adapter (HBA) vendors. In this architecture, the IMA Common Library includes a set of APIs for managing HBAs.
“The IMA library will improve [vendors’] time-to-market because of decreased integration and test costs,” says Matthew Brisse, a technology strategist at Dell and vice chair of the SNIA board of directors. “For IT users, IMA will increase interoperability between iSCSI HBAs and management applications through a standard interface.”
The SNIA plans to submit the IMA to the InterNational Committee for Information Technology Standards (INCITS). The SNIA plans a similar path for its Multipath Management API (MMA), which was recently approved.
Multi-path management allows multiple I/O connections between hosts and devices, providing redundancy and increased bandwidth. The MMA plug-in architecture allows vendors with multi-path drivers to expose management capabilities through a common API.
Brisse says MMA benefits IT users by enabling management applications to discover multi-path devices and associated ports, independent of the vendor. With the active management option, MMA provides fail-over, load balancing, and manual path overrides.
The SNIA’s Common RAID DDF standard has also been submitted to INCITS. DDF standardizes the way data is distributed across drives in a RAID array. (For more information on the DDF standard, see “Solving the RAID compatibility puzzle,” InfoStor, January 2005, p. 38.)
“RAID 5, for example, is not the same across vendors,” says Brisse. “DDF provides a common way for data to be organized on disks.” This will result in better interoperability, allowing “data-in-place” movement from RAID on the motherboard (ROMB) structures to external disks with less chance of data loss. In addition, RAID 6 was recently added to the DDF specification.
Dunn says that all of the work being done by the SNIA is guided by users’ top-10 pain points that were identified in its spring 2004 End User Council (EUC) survey. According to the 500 respondents, the top four were cost, growth, manageability, and interoperability.
Dunn says, “We use the EUC survey as our litmus test for the work we’re doing. We continually ask ourselves, ‘How does this relate to the EUC pain points?’ ”