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Patent Trials and Appeals Board

Oct 22, 2019

14446191 - (D) (P.T.A.B. Oct. 22, 2019)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
14/446,191 07/29/2014 Anil Nanduri 90470444 5089
56436 7590 10/22/2019
Hewlett Packard Enterprise
3404 E. Harmony Road
Mail Stop 79
Fort Collins, CO 80528
EXAMINER
WESTBROOK, MICHAEL L
ART UNIT PAPER NUMBER
2139
NOTIFICATION DATE DELIVERY MODE
10/22/2019 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
chris.mania@hpe.com
hpe.ip.mail@hpe.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________________

Ex parte ANIL NANDURI, CHUNQI HAN, and
MURALI KRISHNA VISHNUMOLAKALA
____________________

Appeal 2019-000867
Application 14/446,1911
Technology Center 2100
____________________
Before J. JOHN LEE, DANIEL J. GALLIGAN, and
DAVID J. CUTITTA II, Administrative Patent Judges.
GALLIGAN, Administrative Patent Judge.
DECISION ON APPEAL
Introduction
Appellant appeals under 35 U.S.C. § 134(a) from a final rejection of
claims 1–3, 5, 6, 8, 10, 11, 13, 14, 16, 18, 19, and 21–24, which are all of the
claims pending in the application. We have jurisdiction under 35 U.S.C.
§ 6(b). Claims 4, 7, 9, 12, 15, 17, and 20 have been cancelled.
We AFFIRM IN PART.2

1 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. Appellant identifies the real party in interest as Hewlett
Packard Enterprise Development LP. Appeal Br. 3.
2 Our Decision refers to Appellant’s Appeal Brief filed May 10, 2018
(“Appeal Br.”); Appellant’s Reply Brief filed November 13, 2018 (“Reply
Br.”); Examiner’s Answer mailed September 10, 2018 (“Ans.”); and Final
Office Action mailed November 1, 2017 (“Final Act.”).
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Application 14/446,191

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STATEMENT OF THE CASE
Claims on Appeal
Claims 1, 11, and 16 are independent claims. Claim 1 is reproduced
below:
1. A method for a storage system having a storage controller
communicatively coupled to a storage array, the storage
controller comprising a processor, volatile memory and non-
volatile memory, and the storage array having a plurality of
storage drives, the method comprising:
maintaining, by the storage controller external to each of
the storage drives, a single segment map for all of the storage
drives in a persistent storage, each entry of the segment map
mapping a segment identifier to a stripe number;
prior to a first one of the storage drives failing, processing
by the storage controller a first sequence of write requests, the
first sequence of write requests being associated with a first
sequence of the segment identifiers;
when the first storage drive fails and becomes
unresponsive to any requests, storing by the storage controller a
first one of the segment identifiers from the segment map on a
plurality of the storage drives other than the failed first storage
drive, the first segment identifier being associated with the last
data segment to be fully written to the storage array prior to the
failure of the first storage drive;
subsequent to the first storage drive failing, processing by
the storage controller a second sequence of write requests, the
second sequence of write requests being associated with a second
sequence of the segment identifiers;
subsequent to the first storage drive being recovered,
determining by the storage controller data segments associated
with content to be rebuilt on the first storage drive, wherein the
determination by the storage controller is based on the first
segment identifier and the single segment map for all of the
storage drives; and
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rebuilding, by the storage controller and on the first
storage drive, content of data segments corresponding to ones of
the segment identifiers that are greater than the first segment
identifier.
References
Fellin
Tseng
Watanabe
Yang
US 2004/0078637 A1
US 2006/0161805 A1
US 2014/0089730 A1
US 2015/0127891 A1
Apr. 22, 2004
July 20, 2006
Mar. 27, 2014
May 7, 2015
Examiner’s Rejections
Claims 1–3, 5, 6, 8, 11, 13, 14, 16, 18, 19, and 22–24 stand rejected
under 35 U.S.C. § 103 as being unpatentable over Fellin and Tseng. Final
Act. 2–16.
Claim 10 stands rejected under 35 U.S.C. § 103 as being unpatentable
over Fellin, Tseng, and Watanabe. Id. at 17–18.
Claim 21 stands rejected under 35 U.S.C. § 103 as being unpatentable
over Fellin, Tseng, and Yang. Id. at 18–20.

ANALYSIS
Obviousness: Claims 1–3, 8, 10, 11, 16, and 21–24
Appellant argues the Examiner erred in finding the combination of
Fellin and Tseng teaches a “storage controller external to each of the storage
drives,” and “storing by the storage controller a first one of the segment
identifiers from the segment map on a plurality of the storage drives other
than the failed first storage drive,” as recited in claim 1 and similarly recited
in claims 11 and 16. Appeal Br. 9–13; Reply Br. 4–10. In particular,
Appellant argues that the “process of Fellin is performed directly between a
current replica and a recovering replica” but that the claimed process “is not
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performed directly between two storage drives” and instead is performed by
“a storage controller external to each of the storage drives.” Appeal Br. 10–
11 (emphasis omitted); Reply Br. 5. Further, Appellant argues Tseng’s
storage controller does not store “a first one of the segment identifiers from
the segment map on a plurality of the storage drives other than the failed
first storage drive.” Appeal Br. 12; Reply Br. 7. Additionally, Appellant
argues Fellin stores segment identifiers “on a single one of the non-failed
replicas” rather than “on a plurality of the storage drives other than the
failed first drive.” Appeal Br. 11–12; Reply Br. 6–7.
We are not persuaded. The Examiner finds, and we agree, Fellin
teaches “storing by the storage controller a first one of the segment
identifiers . . . on a plurality of the storage drives other than the failed first
storage drive.” Final Act. 4–5. The Examiner’s finding relies on Fellin’s
description of a data storage system that includes a source device, i.e., a
“storage controller,” a recovering replica drive, i.e., a “failed first storage
drive,” current replica drives, i.e., “storage drives other than the failed first
storage drive,” and write request sequence numbers, i.e., “segment
identifiers.” Ans. 4 (citing Fellin Fig. 1); Final Act. 3–5 (citing Fellin ¶¶ 13–
14, 43–44, Abstract). Notably, Fellin describes that, in a recovery process
for a recovering replica, a replica that does not require recovery, i.e., a
“current replica[,] receives the identity of the last consecutive write request
sent by the source that the recovering replica received before missing a write
request” and further that “the current replica receives new write requests
from the source.” Fellin ¶ 13; see id. Abstract. The Examiner further finds,
and we agree, Tseng teaches a “storage controller external to each of the
storage drives,” which stores “segment identifiers from the segment map.”
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Final Act. 8; Ans. 4. In particular, the Examiner relies on Tseng’s storage
controller, external to a RAID array of storage drives (Tseng Fig. 2), to
perform and track a storage drive recovery process via the storage
controller’s differential rebuild (DR) apparatus (id. ¶ 64). The storage
controller’s storage drive recovery process uses a “WIP map” that is
“configured with a WIP map entry for each stripe group of the RAID array,”
i.e., a segment map. Id. ¶ 65.
Appellant’s arguments that Fellin does not teach “a storage controller
external to each of the storage drives” (Appeal Br. 11; Reply Br. 5) and that
Tseng does not teach storing “a first one of the segment identifiers from the
segment map on a plurality of the storage drives other than the failed first
storage drive” (Appeal Br. 12; Reply Br. 7) inappropriately attack Fellin and
Tseng individually when the Examiner relies on the combination of Fellin
and Tseng. See In re Keller, 642 F.2d 413, 426 (CCPA 1981) (citation
omitted). The Examiner relies on Tseng to teach an “external storage
controller to perform the recovery process.” Ans. 4. And the Examiner
relies on Fellin to teach segment identifiers stored on replica drives in a
recovery process. Final Act. 5. The Examiner finds the combination of
Fellin and Tseng teaches the disputed limitation and provides reasoning to
combine the teachings of the references. Ans. 5–6; Final Act. 9. However,
Appellant’s arguments do not address that combination and instead address
Fellin and Tseng individually. As such, those arguments are unpersuasive of
Examiner error.
Moreover, even considering Fellin individually for argument’s sake,
we disagree with Appellant’s argument that Fellin does not teach “a storage
controller external to each of the storage drives that controls the storage
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drives . . . to perform the recovery process.” Appeal Br. 11; Reply Br. 5. In
Fellin, a source device external to Fellin’s replica drives (Fellin Fig. 1) sends
a “response” to a replica drive to signal that the replica drive needs to
“recover” data due to some failure (id. ¶ 56). During the recovering
replica’s recovery process, the source device transmits to a current replica
“the identity of the last consecutive write request sent by the source that the
recovering replica received” as well as “new write requests from the
source.” Id. ¶ 13, Fig. 1; see id. ¶ 61. Those write requests have
corresponding sequence numbers, i.e., segment identifiers, stored by the
current replica drive. Id. ¶ 43. As such, Fellin’s source device causes the
storage of segment identifiers on current replica drives that are not the
recovering replica drive. Accordingly, we agree with the Examiner’s
finding that Fellin teaches “a storage controller external to each of the
storage drives that controls the storage drives . . . to perform the recovery
process,” within the meaning of the claims. Ans. 4.
Additionally, Appellant’s argument that Fellin stores segment
identifiers “on a single one of the non-failed replicas” rather than “on a
plurality of the storage drives other than the failed first drive” (Appeal
Br. 11–12; Reply Br. 6–7) is not persuasive because that argument fails to
address the Examiner’s determination that it would have been obvious to
store segment identifiers on a plurality of storage drives in view of Fellin
(Final Act. 5–6; Ans. 6). In particular, Appellant does not address the
Examiner’s determination that “it would have been obvious . . . to store the
first segment identifier in prior art Fellin on more than one replica storage
drive” because doing so would “increase reliability and ensure recovery of
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the recovering replica by storing recovery information (i.e. first segment
identifier) on more than one storage drive.” Final Act. 6.
Furthermore, even if we were to consider, for argument’s sake,
Appellant’s untimely Reply Brief arguments addressing the Examiner’s
obviousness determination (Reply Br. 8–103), Fellin itself supports the
Examiner’s obviousness determination because Fellin teaches, or at least
suggests, storing segment identifiers “on a plurality of the storage drives.”
In particular, Fellin describes that its “multiple replicas 102 each contain the
same data and provide backup for one another in the event of the failure of
one or more of the replicas. The source 101 sends write requests to all of the
replicas 102 . . . .” Fellin ¶ 41; see id. ¶ 14 (disclosing that “the assigned
sequence number of a write request is sent to each replica, and it is stored by
the replica” and that “[e]ach replica also maintains . . . the sequence number
of the highest write request ever processed by the replica.”). Thus, Fellin
teaches, or at least suggests, that write requests and associated segment
identifiers are written to all replica drives.
Accordingly, we are not persuaded the Examiner erred in finding the
combination of Fellin and Tseng teaches or suggests a “storage controller
external to each of the storage drives” and “storing by the storage controller
a first one of the segment identifiers from the segment map on a plurality of
the storage drives other than the failed first storage drive,” as recited in

3 The Examiner determined, in the Final Action, that it would have been
obvious to modify Fellin such that the first segment identifier is stored on
more than one replica storage drive (Final Act. 5–6), but Appellant’s Appeal
Brief did not address that determination (see Appeal Br. 9–13).
Accordingly, Appellant’s Reply Brief arguments are untimely. See 37
C.F.R. § 41.41(b)(2).
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claim 1 and similarly recited in claims 11 and 16, not separately argued.
Appeal Br. 13. Appellant does not argue separate patentability for
dependent claims 2, 3, 8, 10, and 21–24, which depend directly or indirectly
from claims 1, 11, and 16. See Appeal Br. 9–16. Accordingly, for the
reasons set forth above, we sustain the Examiner’s decision to reject claims
1–3, 8, 10, 11, 16, and 21–24.

Obviousness: Claims 5, 6, 13, 14, 18, and 19
Appellant argues the Examiner erred in finding Fellin teaches “storing
an identifier of the first storage drive on the plurality of the storage drives
other than the failed first storage drive,” as recited in claim 5 and similarly
recited in claims 13 and 18. Appeal Br. 13–14; Reply Br. 11. Specifically,
Appellant argues that, although Fellin identifies a failed storage drive, Fellin
does not describe storing an identifier of that failed storage drive on another
storage drive. Appeal Br. 13; Reply Br. 11.
We are persuaded the Examiner erred. The claims require that the
identity of the failed drive is stored on drives that have not failed. The
Examiner asserts that “under broadest reasonable interpretation, the prior
art’s identification of the failed replica corresponds to . . . a storage drive
storing an identifier (i.e. identifying) of the failed storage drive.” Ans. 8;
Final Act. 10 (citing Fellin ¶ 42). Although the Examiner is correct that
Fellin describes identifying a failed storage drive, it does not necessarily
follow that Fellin also stores an identifier for that failed drive “on the
plurality of the storage drives other than the failed first storage drive.” The
Examiner has not explained how, and we do not readily ascertain where, the
cited portions of Fellin describe storing the identity of a failed drive on a
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“plurality” of drives that have not failed. Nor has the Examiner concluded
that it would have been obvious to store an identifier of a failed drive “on the
plurality of the storage drives other than the failed first storage drive” in
view of Fellin.
Accordingly, we are constrained by the record to reverse the
Examiner’s obviousness rejection of dependent claims 5, 13 and 18. Claims
6, 14, and 19 depend from claims 5, 13, and 18, and stand with claims 5, 13,
and 18. Therefore, we do not sustain the rejections of claims 5, 6, 13, 14,
18, and 19 under 35 U.S.C. § 103.

CONCLUSION
In summary:
Claims
Rejected
35 U.S.C. § Basis Affirmed Reversed
1–3, 5, 6, 8,
11, 13, 14,
16, 18, 19,
22–24
103 Fellin, Tseng 1–3, 8, 11,
16, 22–24
5, 6, 13,
14, 18, 19
10 103 Fellin, Tseng,
Watanabe
10
21 103 Fellin, Tseng, Yang 21
Overall
Outcome
1–3, 8, 10,
11, 16,
21–24
5, 6, 13,
14, 18, 19

No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 41.50(f).
AFFIRMED IN PART