Cross tagging to data for consistent recovery
DC CAFCFirst Claim
1. A system for consistent data recovery, comprising a storage area network (SAN) of initiator nodes and target nodes, wherein initiator nodes issue I/O requests and target nodes respond to I/O requests, the SAN being represented logically as a plurality of consistency groups of nodes, G1, . . . , Gn, each consistency group representing:
- (A) at least one logical storage unit (LU), each LU acting as a target node within the SAN;
(B) at least one host device, each host device acting as an initiator within the SAN, each host device comprising (B.1) a transmitter for issuing I/O requests to at least one LU, and each host device being associated with (C) a host device agent, the host device agent comprising;
(C.1) an interceptor for intercepting I/O requests issued by the host device and performing one or more of sending the intercepted I/O requests to the at least one LU, redirecting the intercepted I/O request to another LU, splitting the intercepted I/O requests to enable sending of the intercepted I/O requests first to a data protection agent prior to transmission to the at least one LU; and
(C.2) a router for forwarding the intercepted I/O requests to the data protection appliance;
(D) a data protection appliance (DPA) acting as both an initiator node and a target node within the SAN, the DPA comprising;
(D.1) a receiver for receiving a current I/O request forwarded by an agent router for a host device;
(D.2) a router for forwarding the current I/O request to a replication facility;
(D.3) an ACK transmitter for sending an acknowledgement for an I/O request to an agent, wherein said agent router is operable to halt forwarding further host device I/O requests until the acknowledgement for a current I/O request is received from the DPA, and to resume forwarding after the acknowledgement for the current I/O request is received; and
(D.4) a tag initiator for issuing an instruction for the replication facility to tag a consistency group at a current point in time; and
(E) a replication facility comprising;
(E.1) a receiver for receiving I/O requests forwarded by said DPA router; and
(E.2) a data recoverer for restoring the LUs to a tagged state, based on I/O requests received by said DPA receiver,the system further comprising (F) a DPA manager operable to send requests to said DPAs of G1, . . . , Gn,(r1) to stop their ACK transmitters sending acknowledgements for I/O requests to said host device agents of G1, . . . , Gn, and(r2) to tag G1, . . . , Gn.
12 Assignments
Litigations
1 Petition
Accused Products
Abstract
A system for consistent data recovery, including a storage area network (SAN) of initiator nodes and target nodes, wherein initiator nodes issue I/O requests and target nodes respond to I/O requests, the SAN being represented logically as a plurality of consistency groups of nodes, G1, . . . , Gn, each consistency group representing at least one logical storage unit (LU), each LU acting as a target node within the SAN, at least one host device, each host device acting as an initiator within the SAN, each host device including a transmitter for issuing I/O requests to at least one LU, and each host device being associated with a host device agent, the host device agent including an interceptor for intercepting I/O requests issued by the host device, and a router for forwarding the intercepted I/O requests to a data protection appliance, a data protection appliance (DPA) acting as both an initiator node and a target node within the SAN.
-
Citations
46 Claims
-
1. A system for consistent data recovery, comprising a storage area network (SAN) of initiator nodes and target nodes, wherein initiator nodes issue I/O requests and target nodes respond to I/O requests, the SAN being represented logically as a plurality of consistency groups of nodes, G1, . . . , Gn, each consistency group representing:
-
(A) at least one logical storage unit (LU), each LU acting as a target node within the SAN; (B) at least one host device, each host device acting as an initiator within the SAN, each host device comprising (B.1) a transmitter for issuing I/O requests to at least one LU, and each host device being associated with (C) a host device agent, the host device agent comprising; (C.1) an interceptor for intercepting I/O requests issued by the host device and performing one or more of sending the intercepted I/O requests to the at least one LU, redirecting the intercepted I/O request to another LU, splitting the intercepted I/O requests to enable sending of the intercepted I/O requests first to a data protection agent prior to transmission to the at least one LU; and (C.2) a router for forwarding the intercepted I/O requests to the data protection appliance; (D) a data protection appliance (DPA) acting as both an initiator node and a target node within the SAN, the DPA comprising; (D.1) a receiver for receiving a current I/O request forwarded by an agent router for a host device; (D.2) a router for forwarding the current I/O request to a replication facility; (D.3) an ACK transmitter for sending an acknowledgement for an I/O request to an agent, wherein said agent router is operable to halt forwarding further host device I/O requests until the acknowledgement for a current I/O request is received from the DPA, and to resume forwarding after the acknowledgement for the current I/O request is received; and (D.4) a tag initiator for issuing an instruction for the replication facility to tag a consistency group at a current point in time; and (E) a replication facility comprising; (E.1) a receiver for receiving I/O requests forwarded by said DPA router; and (E.2) a data recoverer for restoring the LUs to a tagged state, based on I/O requests received by said DPA receiver, the system further comprising (F) a DPA manager operable to send requests to said DPAs of G1, . . . , Gn, (r1) to stop their ACK transmitters sending acknowledgements for I/O requests to said host device agents of G1, . . . , Gn, and (r2) to tag G1, . . . , Gn. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A method for consistent data recovery, comprising issuing requests from a data protection appliance (DPA) manager to at least one DPA within at least one consistency group, G1, . . . , Gn,
(r1) to stop sending acknowledgements of I/O requests to host device agents of G1, . . . , Gn, and (r2) to tag G1, . . . , Gn, wherein a tag is used to mark a consistency group at a specific point in time, wherein the consistency groups G1, . . . , Gn represent logical parts of a storage area network, and each consistency group G1, . . . , Gn represents a DPA, at least one host device, at least one LU and at least one replication facility, the replication facility being operable to restore the at least one LU to its former state at the time of the tag, and wherein each host device is associated with a host device controller that is operable to: -
forward the host device I/O requests; halt such forwarding when it does not receive an acknowledgement of a current I/O request from a DPA; and resume such forwarding after it does receive an acknowledgement of the current I/O request from the DPA. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A computer-readable storage medium storing program code for causing a data protection appliance (DPA) manager to issue requests to at least one DPA within at least one other consistency group, G1, . . . , Gn,
(r1) to stop sending acknowledgements of I/O requests to host device agents of G1, . . . , Gn, and (r2) to tag G1, . . . , Gn, wherein a tag is used to mark a consistency group at a specific point in time, wherein the consistency groups G1, . . . , Gn represent logical parts of a storage area network, and each consistency group G1, . . . , Gn represents a DPA, at least one host device, at least one LU and at least one replication facility, the replication facility being operable to restore the at least one LU to its former state at the time of the tag, and wherein each host device is associated with a host device agent that is operable to: -
forward the host device I/O requests; halt such forwarding when it does not receive an acknowledgement of a current I/O request from a DPA; and resume such forwarding after it does receive an acknowledgement of the current I/O request from the DPA.
-
-
19. A system for data protection, comprising a network represented logically as a plurality of consistency groups, G1, . . . , Gn, each consistency group representing:
-
at least one host device for issuing I/O requests, and each host device being associated with a host device controller for processing I/O requests issued by the host device; and a data protection appliance (DPA), communicating with said at least one host device, comprising; a quiesce controller operable to cause said at least one host device controller to halt processing I/O requests and to cause said at least one host device controller to resume processing I/O requests; and a tag initiator for marking a specific consistency group at a specific point in time; the system further comprising a DPA manager operable to send requests to said DPAs of G1, . . . , Gn, (r1) via their quiesce controllers, to cause said host device controllers of G1, . . . , Gn to halt processing I/O requests, and (r2) to initiate tags in G1, . . . , Gn. - View Dependent Claims (20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32)
-
-
33. A method for data protection, comprising issuing requests from a data protection appliance (DPA) manager, to at least one DPA within at least one consistency group, G1, . . . , Gn, the request comprising:
-
(r1) to cause host device controllers of G1, . . . , Gn to halt processing I/O requests, and (r2) to initiate tags in G1, . . . , Gn, wherein a tag is used to mark a consistency group at a specific point in time, wherein the consistency groups G1, . . . , Gn represent logical parts of a network, and each consistency group G1, . . . , Gn represents a DPA and at least one host device, and wherein each host device is associated with a host device controller that processes the host device I/O requests, and that can halt such processing and that can resume such processing. - View Dependent Claims (34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44)
-
-
45. A computer-readable storage medium storing program code for causing a data protection appliance (DPA) manager to issue requests to at least one DPA within at least one consistency group, G1, . . . , Gn, the requests comprising:
-
(r1) to cause host device controllers of G1, . . . , Gn to halt processing I/O requests, and (r2) to initiate tags in G1, . . . , Gn, wherein a tag is used to mark a consistency group at a specific point in time, wherein the consistency groups G1, . . . , Gn represent logical parts of a network, and each consistency group G1, . . . , Gn represents a DPA and at least one host device, and wherein each host device is associated with a host device controller that processes the host device I/O requests, and that can halt such processing and that can resume such processing.
-
-
46. A system for data recovery to a crash consistent state of data of a plurality of consistency groups stored in a storage sub-system, comprising:
-
(A) a storage area network (SAN) of initiator nodes and target nodes, wherein initiator nodes issue I/O requests and target nodes respond to I/O requests, the SAN comprising; (A.1) at least one storage subsystem acting as a SAN target node, comprising; (A.1.1) at least one addressable physical storage unit; and (A.1.2) at least one controller operable to provide access to data stored in said at least one addressable physical storage unit, to at least one host acting as a SAN initiator node through at least one logical storage unit (LU), each LU having an identifier; and (A.2) at least one host acting as a SAN initiator node, operable to issue I/O requests to said at least one LU through at least one host device, each host device having an identifier; (B) at least one data processing unit, each data processing unit comprising; (B.1) a receiver for receiving I/O requests issued by at least one host to at least one LU; (B.2) a router for forwarding a current I/O request to a data protection facility; and (B.3) a transmitter for sending an acknowledgement for an I/O request to a host device of said at least one host, wherein each of said at least one host is operable to halt processing further I/O requests through a host device until the acknowledgement is received from the data processing unit for a current I/O request, and to resume processing I/O requests through a host device after the acknowledgement is received; (C) at least one consistency group, each consistency group being a logical entity comprising; (C.1) an identifier; (C.2) at least one of the LU identifiers; and (C.3) at least one of the host device identifiers; (D) a tag initiator for issuing an instruction for the data protection facility to store a consistency group identifier and a tag identifier; and (E) a data protection facility comprising; (E.1) a receiver for receiving I/O requests forwarded by said at least one router; and (E.2) a journal processor for storing write I/O requests issued to at least one LU, each write I/O request comprising an identifier of the LU to which the I/O request was issued and an identifier of the sequential order of the write request; and (E.3) a data recoverer for processing the data stored by said journal processor and the data stored in said at least one LU, or a copy thereof, so to enable at least one SAN initiator node to process the at least one LU, or a copy thereof, in a state it was in at least one point in time in the past, wherein one of the data processing units of the system further comprises (B.4) a data protection manager operable to send requests, via said transmitter, to at least one data processing unit, (r1) to halt host devices of at least one consistency group handled by that data processing unit, and (r2) to tag a consistency group.
-
Specification