Overview: The Next Generation Mass Storage Stack (September 2009)
Table Of Contents
- Abstract
- Background
- Features of the Next Generation Mass Storage Stack
- Impact
- Background
- Impact
- Background
- Impact
- Background
- Impact
- Impact
- Introduction to the Agile View
- Changes to I/O and Mass Storage Subsystems
- Changes to Other Subsystems
- Migrating to the Agile View
- Conclusion
- Glossary
- Appendix A: Summary of Changes
- Appendix B: Using ioscan
- Appendix C: Using scsimgr
- Appendix D: Interpreting Lunpath Hardware Paths
- For more information
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Lunpath Hardware Path
The representation of a hardware path for a mass storage device. It is identical in format to a legacy
hardware path up to the HBA. After the HBA, additional addressing is represented in hexadecimal
format. The string 0/2/1/0.0x50001fe1500170ac.0x4017000000000000 is an example of a lunpath
hardware path.
Multi-pathing
The detection, correlation, and coordinated usage of multiple hardware paths leading to the same LUN.
Pass-Through DSF
A DSF that enables direct access to SCSI devices. The esctl pass-through driver enables support of
devices which are not normally supported by the esdisk, estape, and eschgr drivers.
Persistent DSF
A DSF conforming to the naming model introduced in HP-UX 11i v3 to support agile addressing. The
device file name contains an instance number, such as /dev/disk/disk#, and the minor number has
no hardware path information.
Persistent LUN Binding
See Agile Addressing.
WWID
Worldwide Identifier. A unique identifier for a SCSI device obtained from EVPD INQUIRY page 0x83 of
id_type 1, 2, 3, 7, 8 and an association of 0.