US6647474B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Remote data mirroring system using local and remote write pending indicators
Assignee: EMC Corp
•
Filing: 2002-08-20
•
Granted: 2003-11-11
•
Expires: 2022-08-20
Abstract
Abstract A primary data storage system is linked to a geographically remote secondary data storage system for automatically maintaining a remote copy of the data in the primary storage. The primary data storage system controller uses write pending indicators to control and coordinate the remote copy process. In response to receipt of data from the host computer, a first write pending indicator is set to write the data into at least one primary data storage device, and a second write pending indicator is set to copy the data to the secondary data storage system controller. The first write pending indicator is reset after the data is written to the primary data storage device, and the second write pending indicator is reset after receiving an acknowledgement back from the secondary data storage system controller.
Inventors
- 👤 Moshe Yanai
- 👤 Natan Vishlitzky
- 👤 Bruno Alterescu
- 👤 Daniel D. C. Castel
- 👤 Gadi G. Shklarsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:12
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/16; G06F11/20; G06F11/2053; G06F11/2056; G06F11/2071; G06F11/2066; G06F11/2074; G06F11/2079; G06F11/2082; G06F3/00; G06F3/06; G06F3/0601; G06F3/0602; G06F3/0608; G06F3/061; G06F3/0614; G06F3/0619; G06F3/0628; G06F3/0638; G06F3/064; G06F3/0646; G06F3/0647; G06F3/065; G06F3/0655; G06F3/0661; G06F3/0668; G06F3/067; G06F3/0671; G06F3/0683; G06F3/0689; H; H04; H04L; H04L67/00; H04L67/01; H04L67/10; H04L67/1095; H04L69/00; H04L69/40; H04L9/00; H04L9/40; G11; G11B; G11B20/00; G11B20/10; G11B20/12; G11B20/1217; H04L69/26; Y; Y10; Y10S; Y10S707/00; Y10S707/99941; Y10S707/99942
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
317 words
A remote copy system for automatically providing a remote copy of data from a host computer, said system comprising: a first data storage system including a first data storage system controller and at least one first data storage device, the first data storage system controller having a first cache memory, the first data storage system controller receiving the data from the host computer and initially storing the data in the first cache memory and subsequently writing the data into said at least one first data storage device; and a second data storage system located remote from the first data storage system, the second data storage system including a second data storage system controller and at least one second data storage device, the second data storage system controller having a second cache memory, the first data storage system controller being coupled to the second data storage system controller for copying the data from the first data storage system controller to the second data storage system controller, the second data storage system controller storing the data in the second cache memory and writing the data into said at least one second data storage device to produce the remote copy of the data from the host computer; the first data storage system controller coordinating and controlling the copying of the data to the second data storage system controller wherein, in response to receipt of the data from the host computer, a first write pending indicator is set to write the data into said at least one first data storage device, and a second write pending indicator is set to copy the data to the second data storage system controller, the first write pending indicator being reset after the data is written to said at least one first data storage device and the second write pending indicator being reset after receiving an acknowledgement back from the second data storage system controller.
Claim 2
Dependent Claim
317 words
A remote copy system for automatically providing a remote copy of data from a host computer, said system comprising: a first data storage system including a first data storage system controller and at least one first data storage device, the first data storage system controller having a first cache memory, the first data storage system controller receiving the data from the host computer and initially storing the data in the first cache memory and subsequently writing the data into said at least one first data storage device; and a second data storage system located remote from the first data storage system, the second data storage system including a second data storage system controller and at least one second data storage device, the second data storage system controller having a second cache memory, the first data storage system controller being coupled to the second data storage system controller for copying the data from the first data storage system controller to the second data storage system controller, the second data storage system controller storing the data in the second cache memory and writing the data into said at least one second data storage device to produce the remote copy of the data from the host computer; the first data storage system controller coordinating and controlling the copying of the data to the second data storage system controller wherein, in response to receipt of the data from the host computer, a first write pending indicator is set to write the data into said at least one first data storage device, and a second write pending indicator is set to copy the data to the second data storage system controller, the first write pending indicator being reset after the data is written to said at least one first data storage device and the second write pending indicator being reset after receiving an acknowledgement back from the second data storage system controller.
Claim 3
Dependent Claim
33 words
The remote copy system as claimed in claim 1 , wherein the acknowledgement back from the second data storage system controller indicates that the second data storage system controller has received the data.
Claim 4
Dependent Claim
38 words
The remote copy system as claimed in claim 1 , wherein the acknowledgement back from the second data storage system controller indicates that the data has actually been written to said at least one second data storage device.
Claim 5
Dependent Claim
55 words
The remote copy system as claimed in claim 1 , wherein the first data storage system returns an i/o completion signal to the host computer, and the data is copied to the second data storage system asynchronously from the time when the first data storage system returns the i/o completion signal to the host computer.
Claim 6
Dependent Claim
58 words
The remote copy system as claimed in claim 1 , wherein the first data storage system controller returns an i/o completion signal to the host computer after the data has been safely stored in both the first data storage system and in the second data storage system as indicated by the acknowledgement from the second data storage system.
Claim 7
Dependent Claim
68 words
The remote copy system as claimed in claim 1 , wherein the first data storage system controller includes at least one disk adapter for writing the data from the first cache memory to said at least one first data storage device, and said at least one disk adapter resets the first write pending indicator when it writes the data to said at least one first data storage device.
Claim 8
Dependent Claim
37 words
The remote copy system as claimed in claim 1 , wherein the second write pending indicator is reset when the second data storage system has written the data to said at least one second data storage device.
Claim 9
Dependent Claim
39 words
The remote copy system as claimed in claim 1 , wherein the copying of the data from the first data storage system to the second data storage system is controlled independent of and without intervention from any host computer.
Claim 10
Dependent Claim
28 words
The remote copy system as claimed in claim 1 , wherein the first and second write pending indicators are flags in at least one table of flag bits.
Claim 11
Dependent Claim
38 words
The remote copy system as claimed in claim 9 , wherein said at least one table of flag bits is maintained by the first data storage system and kept on said at least one first data storage device.
Claim 12
Dependent Claim
74 words
The remote copy system as claimed in claim 1 , wherein the first and second write pending indicators are flags in a first table of flag bits maintained by the first data storage system and kept on said at least one first data storage device, and the flags are also kept on said at least one second data storage device in a second table of flag bits maintained by the second data storage system.
Claim 13
Dependent Claim
423 words
A remote copy system for automatically providing a geographically remote copy of data from a host computer, said system comprising: a first data storage system including a first data storage system controller and at least one first data storage device, the first data storage system controller having a first cache memory, the first data storage system controller receiving the data from the host computer and initially storing the data in the first cache memory and subsequently writing the data into said at least one first data storage device; and a second data storage system geographically removed from the first data storage system, the second data storage system including a second data storage system controller and at least one second data storage device, the second data storage system controller having a second cache memory, the first data storage system controller being coupled to the second data storage system controller for copying the data from the first data storage system controller to the second data storage system controller, the second data storage system controller storing the data in the second cache memory and writing the data into said at least one second data storage device to produce the remote copy of the data from the host computer independent of the host computer; the first data storage system controller coordinating and controlling the copying of the data to the second data storage system controller wherein, in response to receipt of the data from the host computer, when the data is stored into the first cache memory, a first write pending indicator is set to write the data into said at least one first data storage device, and a second write pending indicator is set to copy the data to the second data storage system controller, the first write pending indicator being reset after the data is written to said at least one first data storage device and the second write pending indicator being reset after receiving an acknowledgement back from the second data storage system controller that the data has at least been received by the second data storage system controller; wherein the first data storage system returns an i/o completion signal to the host computer, and the data is copied to the second data storage system asynchronously from the time when the first data storage system returns the i/o completion signal to the host computer; and wherein the copying of the data from the first data storage system to the second data storage system is controlled independent of and without intervention from any host computer.
Claim 14
Dependent Claim
423 words
A remote copy system for automatically providing a geographically remote copy of data from a host computer, said system comprising: a first data storage system including a first data storage system controller and at least one first data storage device, the first data storage system controller having a first cache memory, the first data storage system controller receiving the data from the host computer and initially storing the data in the first cache memory and subsequently writing the data into said at least one first data storage device; and a second data storage system geographically removed from the first data storage system, the second data storage system including a second data storage system controller and at least one second data storage device, the second data storage system controller having a second cache memory, the first data storage system controller being coupled to the second data storage system controller for copying the data from the first data storage system controller to the second data storage system controller, the second data storage system controller storing the data in the second cache memory and writing the data into said at least one second data storage device to produce the remote copy of the data from the host computer independent of the host computer; the first data storage system controller coordinating and controlling the copying of the data to the second data storage system controller wherein, in response to receipt of the data from the host computer, when the data is stored into the first cache memory, a first write pending indicator is set to write the data into said at least one first data storage device, and a second write pending indicator is set to copy the data to the second data storage system controller, the first write pending indicator being reset after the data is written to said at least one first data storage device and the second write pending indicator being reset after receiving an acknowledgement back from the second data storage system controller that the data has at least been received by the second data storage system controller; wherein the first data storage system returns an i/o completion signal to the host computer, and the data is copied to the second data storage system asynchronously from the time when the first data storage system returns the i/o completion signal to the host computer; and wherein the copying of the data from the first data storage system to the second data storage system is controlled independent of and without intervention from any host computer.
Claim 15
Dependent Claim
38 words
The remote copy system as claimed in claim 12 , wherein the acknowledgement back from the second data storage system controller indicates that the data has actually been written to said at least one second data storage device.
Claim 16
Dependent Claim
68 words
The remote copy system as claimed in claim 12 , wherein the first data storage system controller includes at least one disk adapter for writing the data from the first cache memory to said at least one first data storage device, and said at least one disk adapter resets the first write pending indicator when it writes the data to said at least one first data storage device.
Claim 17
Dependent Claim
37 words
The remote copy system as claimed in claim 12 , wherein the second write pending indicator is reset when the second data storage system has written the data to said at least one second data storage device.
Claim 18
Dependent Claim
28 words
The remote copy system as claimed in claim 12 , wherein the first and second write pending indicators are flags in at least one table of flag bits.
Claim 19
Dependent Claim
38 words
The remote copy system as claimed in claim 16 , wherein said at least one table of flag bits is maintained by the first data storage system and kept on said at least one first data storage device.
Claim 20
Dependent Claim
74 words
The remote copy system as claimed in claim 12 , wherein the first and second write pending indicators are flags in a first table of flag bits maintained by the first data storage system and kept on said at least one first data storage device, and the flags are also kept on said at least one second data storage device in a second table of flag bits maintained by the second data storage system.
Claim 21
Dependent Claim
432 words
A remote copy system for automatically providing a geographically remote copy of data from a host computer, said system comprising: a first data storage system including a first data storage system controller and at least one first data storage device, the first data storage system controller having a first cache memory, the first data storage system controller receiving the data from the host computer and initially storing the data in the first cache memory and subsequently writing the data into said at least one first data storage device; and a second data storage system geographically removed from the first data storage system, the second data storage system including a second data storage system controller and at least one second data storage device, the second data storage system controller having a second cache memory, the first data storage system controller being coupled to the second data storage system controller for copying the data from the first data storage system controller to the second data storage system controller, the second data storage system controller storing the data in the second cache memory and writing the data into said at least one second data storage device to produce the remote copy of the data from the host computer independent of the host computer; the first data storage system controller coordinating and controlling the copying of the data to the second data storage system controller wherein, in response to receipt of the data from the host computer, a first write pending indicator is set to write the data into said at least one first data storage device, and a second write pending indicator is set to copy the data to said second data storage system controller, the first write pending indicator being reset after the data is written to said at least one first data storage device and the second write pending indicator being reset after receiving an acknowledgement back from the second data storage system controller that the data has at least been received by the second data storage system controller; wherein the copying of the data from the first data storage system to the second data storage system is controlled independent of and without intervention from any host computer; and wherein the first and second write pending indicators are flags in a first table of flag bits maintained by the first data storage system and kept on said at least one first data storage device, and the flags are also kept on said at least one second data storage device in a second table of flag bits maintained by the second data storage system.
Claim 22
Dependent Claim
432 words
A remote copy system for automatically providing a geographically remote copy of data from a host computer, said system comprising: a first data storage system including a first data storage system controller and at least one first data storage device, the first data storage system controller having a first cache memory, the first data storage system controller receiving the data from the host computer and initially storing the data in the first cache memory and subsequently writing the data into said at least one first data storage device; and a second data storage system geographically removed from the first data storage system, the second data storage system including a second data storage system controller and at least one second data storage device, the second data storage system controller having a second cache memory, the first data storage system controller being coupled to the second data storage system controller for copying the data from the first data storage system controller to the second data storage system controller, the second data storage system controller storing the data in the second cache memory and writing the data into said at least one second data storage device to produce the remote copy of the data from the host computer independent of the host computer; the first data storage system controller coordinating and controlling the copying of the data to the second data storage system controller wherein, in response to receipt of the data from the host computer, a first write pending indicator is set to write the data into said at least one first data storage device, and a second write pending indicator is set to copy the data to said second data storage system controller, the first write pending indicator being reset after the data is written to said at least one first data storage device and the second write pending indicator being reset after receiving an acknowledgement back from the second data storage system controller that the data has at least been received by the second data storage system controller; wherein the copying of the data from the first data storage system to the second data storage system is controlled independent of and without intervention from any host computer; and wherein the first and second write pending indicators are flags in a first table of flag bits maintained by the first data storage system and kept on said at least one first data storage device, and the flags are also kept on said at least one second data storage device in a second table of flag bits maintained by the second data storage system.
Claim 23
Dependent Claim
68 words
The remote copy system as claimed in claim 19 , wherein the first data storage system controller includes at least one disk adapter for writing the data from the first cache memory to said at least one first data storage device, and said at least one disk adapter resets the first write pending indicator when it writes the data to said at least one first data storage device.
References Cited (Backward Citations)
US3866182A
Cited
US3588839A
Cited
US3623014A
Cited
US3835260A
Cited
US3771137A
Cited
US3936806A
Cited
US4020466A
Cited
US4057849A
Cited
US4150429A
Cited
US4161777A
Cited
US4193113A
Cited
US4084231A
Cited
US4094000A
Cited
US4124843A
Cited
US4249802A
Cited
US4361855A
Cited
US4204251A
Cited
US4342079A
Cited
US4384274A
Cited
US4368532A
Cited
US4594577A
Cited
GB2086625A
Cited
US4523275A
Cited
US4598357A
Cited
US4396984A
Cited
US4464713A
Cited
US4453215A
Cited
US4430727A
Cited
US4523206A
Cited
US4530055A
Cited
US4577272A
Cited
US4608688A
Cited
US4638424A
Cited
US4771375A
Cited
US4755928A
Cited
US4916605A
Cited
US5083271A
Cited
US4959774A
Cited
US4686620A
Cited
US4618827A
Cited
US4634100A
Cited
US4807186A
Cited
US4805106A
Cited
US4707783A
Cited
US4773035A
Cited
US4698808A
Cited
US4751578A
Cited
US4779189A
Cited
US4710870A
Cited
US4841475A
Cited
US5072368A
Cited
US4823333A
Cited
EP0239323A2
Cited
US4726024A
Cited
US4736407A
Cited
US4797750A
Cited
US4814592A
Cited
US4727544A
Cited
US5093787A
Cited
US4769764A
Cited
US4831558A
Cited
US5109492A
Cited
US4866611A
Cited
US4783834A
Cited
US4862411A
Cited
US4785472A
Cited
US4782486A
Cited
US4849978A
Cited
US5123099A
Cited
US5132787A
Cited
US5003382A
Cited
US5087968A
Cited
US5051887A
Cited
US4837680A
Cited
US5099485A
Cited
US5146605A
Cited
US4879718A
Cited
EP0323123B1
Cited
US5175839A
Cited
US5060185A
Cited
US5313664A
Cited
US4974156A
Cited
US5134711A
Cited
US5060142A
Cited
US5159671A
Cited
US4960031A
Cited
US5016876A
Cited
US5007053A
Cited
US4949187A
Cited
US4958270A
Cited
US5089958A
Cited
US5175837A
Cited
US5235687A
Cited
US5170471A
Cited
US5185864A
Cited
US5202887A
Cited
US5239637A
Cited
US5210865A
Cited
US4985695A
Cited
US5029199A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2006-11-10 | 2007-05-12 | 2007-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-11-10 | 2011-05-12 | 2011-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-11-10 | 2015-05-12 | 2015-11-11 | $7700.00 | Window Closed / Lapsed |