Generating updated virtual disks using distributed mapping...

Electrical computers and digital processing systems: memory – Address formation – Address mapping

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C711S103000, C711S200000, C709S217000

Reexamination Certificate

active

07366868

ABSTRACT:
The present invention provides a method for copying data through a virtualized storage system using distributed table driven (I/O) mapping. In a system having a virtual disk (the “original disk”), a persistent mapping table for this virtual disk exists on a controller, and volatile copies of some or all entries in this mapping table are distributed to one or more more mapping agents. The method of the present invention creates a new virtual disk mapping table that has the exact same entries as the mapping table as the original virtual disk. The new snapshot disk then shares the same storage as the original disk, so it is space efficient. Furthermore, creating new snapshot disk involves only copying the contents of the mapping table, not moving data, so the creation is fast. In order to allow multiple virtual disks to share storage segments, writes to either the original virtual disk or the snapshot copy cannot be seen by the other. Therefore, in addition to simply copying the mapping table, both the original and snapshot disk mapping table must also cause writes to these disks to be handled specially. Finally, any changes to the original disk mapping table stored in the controller must be coordinated with the volatile copies stored in the mapping agent in such a way so that all hosts see a consistent view of that disk.

REFERENCES:
patent: 5535381 (1996-07-01), Kopper
patent: 6101585 (2000-08-01), Brown et al.
patent: 6311193 (2001-10-01), Sekido
Montague, Robert M. et al., Virtualizing the SAN, Morgan Keegan & Company, Inc., Jul. 5, 2000, pp. 1-20.
Compaq TechNote for SCO UNIX—Disk Mirroring with VERITAS VxMirror, Dec. 1992, part No. 145656-001.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Generating updated virtual disks using distributed mapping... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Generating updated virtual disks using distributed mapping..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Generating updated virtual disks using distributed mapping... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2760910

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.