<PAGE>

Confidential Materials omitted and filed separately with the Securities and
                Exchange Commission. Asterisks denote omissions.

                                                                    Exhibit 10.8
                                                                    ------------

                          Addendum to EMC Corporation
                          ---------------------------
                    Value Added Systems Integrator Agreement
                    ----------------------------------------

1.  Background/Introduction

  This Addendum dated February 2, 2000 shall be considered an Addendum to the
  Valued Added Systems Integrator Agreement (the "Agreement") between EMC
  Corporation ("EMC") and StorageNetworks, Inc. ("SNI") dated as of September
  15, 1999 (the "VASI").  This Addendum and the Agreement shall be construed
  together.  However, to the extent that this Addendum conflicts with the
  Agreement, this Addendum shall govern.

2.  Pricing Strategy - Volume Purchase Levels

     .    Annual Purchase Commitment: The pricing set forth below provides an
          immediate discount structure based on $50,000,000 year 2000 annual
          commitment.

     .    Quarterly Commitment Levels: To receive this discounted pricing
          structure - SNI agrees that it shall purchase [**] of EMC Products
          direct from EMC during the following calendar quarters in year 2000:

          Q/1                (10%)             $ 5,000,000
          Q/2                (20%)             $10,000,000
          Q/3                (30%)             $15,000,000
          Q/4                (40%)             $20,000,000
          Total 2000 Annual                    $50,000,000


  SNI agrees that [**] or [**] of the $50 million shall be comprised of
  purchases of EMC software products. Each purchase by SNI of [**] of EMC
  products shall consist of at least [**] of EMC software products. Each [**]
  purchase in excess of $50 million shall also consist of at least [**] of EMC
  software products.

     .    Technology Configuration, Costs, Terms and Conditions: All discounts
          throughout YEAR 2000 are based on EMC's list price as of 12/31/99.
          Should EMC reduce its list-pricing , SNI will receive the following
          discount structures off the reduced pricing schedule.

       [**]% MINIMUM FULL FRAME (TOTAL DISKS) with Standard Configuration*
             -------------------------------------------------------------

       3930 Frame (Total disks - [**])            $/MB[**]% Full)
                                                  ----    ------

       [**]% Discount on FRAME, CONNECTIVITY, CACHE      [**]MB
       [**]% Discount on DISK
       [**]% Discount on SOFTWARE                        [**]MB
       NOTE: Less than [**]% full frame, pricing will be [**]MB
       individually based, but revenue will count towards volume commitments ($)

       3830 Frame (Total disks - [**])            $/MB [**]% Full)
                                                  -----    ------

       [**]% Discount on FRAME, CONNECTIVITY, CACHE      [**]MB
       [**]% Discount on DISK
       [**]% Discount on SOFTWARE                        [**]MB
       NOTE: Less than [**]% full frame, pricing will be [**]MB
       individually based, but revenue will count towards volume commitments ($)

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                Exchange Commission. Asterisks denote omissions.

*Standard Symmetrix Configuration (Software): ALL 3830 / 3930 FRAMES CAN BE
CONFIGURED WITH THE FOLLOWING SOFTWARE PRODUCTS:

       -(1) SYMMETRIX CONTROL CENTER PACKAGE
       -(1) TIMEFINDER OPEN
       AND EITHER
       -(2) POWERPATH LICENSES (ENTERPRISE UNIX) OR,
       -(3) POWERPATH LICENSES (ENTERPRISE NT)

       NOTE: ADDITIONAL SOFTWARE PRODUCTS WILL AFFECT THE SW COSTS PER MB.

     .    ANY EMC SOFTWARE REQUIRED BEYOND THE ABOVE LICENSES WILL BE ENTITLED
          TO THE APPROPRIATE DISCOUNT STRUCTURE

Additional Hardware Components

CELERRA (MINIMUM CONFIGURATION)
-------------------------------

 .(1) CFS 14 Celerra Cabinet          [**]% Discount on Celerra Hardware
 .(4) Data Movers
 .(1) Control Station
 .(8) 12mini68S cables
 .(4) NFS Data Mover License          [**]% Discount on Celerra Software
 .(1) Control Station Software

CONNECTRIX (MINIMUM CONFIGURATION)
----------------------------------
 .(1) Connectrix Frame                 [**]% Discount on Connectrix Hardware
 .(1) Connectrix Service Proc Kit
 .(1) 32 Port Director
 .(1) Connectrix Mgr. License          [**]% Discount on Connectrix Software
 .(1) Connectrix Product Mgr. License

HARDWARE UPGRADES (I.e. Individual purchases of Disk, Cache, Connectivity)
--------------------------------------------------------------------------

DISK UPGRADE:                 [**]MB   [**]%  discount off Upgrade List Pricing
CACHE UPGRADE:                [**]     [**]%  discount off Upgrade List Pricing
CONNECTIVITY UPGRADES:        [**]     [**]%  discount off List Pricing
CELERRA HARDWARE UPGRADE:     [**]     [**]%  Discount off List Pricing
CONNECTRIX HARDWARE UPGRADE:  [**]     [**]%  Discount off List Pricing

3.  Special Additional Terms and Discounts:

     Software Site License Pricing:

     SHOULD SNI PURCHASE MULTIPLE COPIES OF EMC SOFTWARE PRODUCTS FOR NEW OR
     EXISTING SYMMETRIX LOCATIONS ON THE SAME ORDER, THE FOLLOWING DISCOUNT
     STRUCTURE WILL APPLY.

VOLUME DISCOUNT
---------------

 . 1 OR MORE COPIES OF ANY EMC SOFTWARE PRODUCT:         [**]% off list
 . 1 - 3 COPIES OF ANY LIKE EMC SOFTWARE PRODUCT:        [**]% off list
 . 4 OR MORE COPIES OF ANY LIKE EMC SOFTWARE PRODUCT:    [**]% off list


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                Exchange Commission. Asterisks denote omissions.

     .    NOTE: ADDITIONAL DISCOUNTS DESCRIBED ABOVE REPLACE THOSE OUTLINED IN
          THE MINIMUM CONFIGURATION FRAMEWORK AND WILL APPLY WHERE APPROPRIATE.

     Software Maintenance:

     TIERED ANNUAL DISCOUNT STRUCTURE WITH ADVANCE COMMITMENT

     12 Month Commitment:      [**]% Discount off List Price on Software and
                                     Hardware Maintenance Fees

     24 Month Commitment:      [**]% Discount off List Price on Software and
                                     Hardware Maintenance Fees

     36 Month Commitment:      [**]% Discount off List Price on Software and
                                     Hardware Maintenance Fees

     Prepayment of any of the: [**]% ADDITIONAL Discount off List price on
     above tiered structure          Software and Hardware Maintenance Fees

     Hardware Maintenance:

     WITH ADVANCE COMMITMENT TO 36 MONTH SOFTWARE MAINTENANCE: 24
     MONTH HARDWARE WARRANTY PERIOD WILL BE EXTENDED TO 36 MONTHS.

     .    ADDITIONAL 12 MONTH COMMITMENTS BEYOND 36 MONTH WARRANTY AT [**]% OFF
          LIST

     .    ADDITIONAL [**]% DISCOUNT FOR PREPAYMENT OF ANY ADDITIONAL 12 MONTH
          COMMITMENT BEYOND 36 MONTH WARRANTY

     .    WITH A 36 MONTH SOFTWARE MAINTENANCE COMMITMENT ON PURCHASES MADE IN
          PAST 90 DAYS, EMC WILL RETROACTIVELY HONOR THE ABOVE DISCOUNTS ON ANY
          SOFTWARE MAINTENANCE INVOICES THAT HAVE NOT BEEN SENT TO SNI AS OF THE
          DATE APPROVAL AND EXECUTION OF THIS ADDENDUM

     General Terms and Conditions:

     .    ALL BASE FRAMES WILL INCLUDE EMC STANDARD REQUIRED CACHE AND MINIMUM
          CONNECTIVITY CARDS AS OUTLINED IN THE STANDARD CONFIGURATION
          DESCRIPTION

     .    ANY EMC HARDWARE OR SOFTWARE PRODUCT (INCLUDING DATA GENERAL AND
          CLARION PRODUCTS) PURCHASED DIRECT FROM EMC WILL APPLY TO THE ANNUAL
          REVENUE COMMITMENT

     .    TO RECEIVE THIS DISCOUNTED PRICING STRUCTURE - SNI AGREES THAT IT
          SHALL PURCHASE 50,000,000 OF EMC PRODUCTS DIRECT FROM EMC DURING THE
          FOUR CALENDAR QUARTERS IN 2000, IN INCREMENTS AS DEFINED ABOVE

     .    IN THE EVENT OF A QUARTERLY PURCHASE SHORTFALL OF [**]% OR LESS(FROM
          THE COMMITMENT, EMC AGREES TO ROLL THIS PURCHASE SHORTFALL INTO THE
          FOLLOWING QUARTERLY COMMITMENT.

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                Exchange Commission. Asterisks denote omissions.

     .    SHOULD THE SHORTFALL EXCEED [**]% SNI AGREES THAT IT WILL PURCHASE A
          SUFFICIENT AMOUNT OF EMC PRODUCT(S) IN ORDER TO FULFILL THE ORIGINAL
          QUARTERLY COMMITMENT.

     .    ON A ONE TIME, ONE QUARTER BASIS, SNI WILL ALSO HAVE AT ITS OPTION,
          THE ABILITY TO PURCHASE EQUIPMENT EQUALING ONLY THE DIFFERENCE BETWEEN
          THE ACTUAL PURCHASES AND [**]% AMOUNT OF THE QUARTER PURCHASE
          COMMITMENT, AND ROLL THE REMAINING [**]% INTO THE FOLLOWING QUARTER.
          THIS OPTION IS AVAILABLE TO SNI FOR ONE QUARTER - Q/1, Q/2 OR Q/3 OF
          2000.

     .    AT THE END OF FISCAL YEAR (Q/4 2000), SHOULD ACTUAL AMOUNT OF
          EQUIPMENT PURCHASED BE LESS THAN 50 MILLION DOLLARS, SNI AGREES THAT
          IT WILL PURCHASE A SUFFICIENT AMOUNT OF EMC PRODUCT(S) IN ORDER TO
          FULFILL THE 50 MILLION DOLLAR ANNUAL COMMITMENT.

     .    FOR ALL PURCHASES IN EXCEES OF ANY QUARTERLY COMMITMENT,THE AMOUNT OF
          SUCH PURCHASES WILL BE APPLIED AS A REDUCTION TOWARDS THE FOLLOWING
          QUARTER'S REVENUE COMMITMENT AND WILL BE ELIGIBLE FOR THE APPLICATION
          OF THE ACCELERATOR DISCOUNT OUTLINED BELOW.

     Accelerator Discounting:

     INCENTIVE DISCOUNT CLAUSE: IN THE EVENT SNI EXCEEDS A STATED QUARTERLY
     PURCHASE COMMITMENT THE NEXT PURCHASE MADE BY SNI AND ANY FOLLOWING
                             ----
     PURCHASES MADE IN SAID QUARTER WILL ENTITLE SNI TO ADDITIONAL
     INDEPENDENT DISCOUNTS (SEE BELOW) ON THE PURCHASE TOTAL FOR: (FRAME,
     CONNECTIVITY AND CACHE), (DISK) AND (SOFTWARE).

            [**]% OFF DOLLAR VALUE OF FRAME, CONNECTIVITY, CACHE
            [**]% OFF DOLLAR VALUE OF DISK
            [**]% OFF DOLLAR VALUE OF SOFTWARE

     EMC Current List Pricing Terms:

     DURING THE TERM OF THIS ADDENDUM, EMC LIST PRICES WILL BE CAPPED ON
     THE START DATE. IF THERE SHOULD BE ANY REDUCTIONS IN LIST PRICES
     DURING THE TERM OF THE AGREEMENT, DISCOUNTING WILL BE APPLIED TO THE
     PRICES IN EFFECT ON THE DATE OF THE SALE.

     Consigned Inventory:

     EMC WILL AGREE TO PROVIDE SNI WITH EMC TECHNOLOGY ON A CONSIGNMENT
     BASIS WITHIN ANY CALENDAR QUARTER.

     NOTE: SNI VPA PRICING ENCLOSED WILL APPLY TO CONSIGNMENT INVENTORY

     TO ENSURE TIMELY DELIVERY, EMC MUST RECEIVE A PURCHASE ORDER FOR
     CONSIGNMENT INVENTORY NO LATER THAN WEEK 10 OF PREVIOUS CALENDAR
     QUARTER DELIVERY OF REQUIRED INVENTORY WILL TAKE PLACE IN THE FIRST
     TWO WEEKS OF A GIVEN QUARTER.

     FAILURE TO DELIVER CONSIGNED INVENTORY PRODUCT WITHIN FIRST TWO WEEKS (14
     DAYS) OF QUARTER WILL ALLOW SNI TO PUSH OUT THE PAYMENT DUE DATE BY AN
     EQUAL AMOUNT OF DAYS LATE. PAYMENT IS DUE BY QUARTER END OR NET 30

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                Exchange Commission. Asterisks denote omissions.

     FROM WHEN TECHNOLOGY BECOMES DEDICATED TO END USER- WHICH EVER COMES FIRST.
     CONSIGNMENT CONFIGURATION: TO BE DEFINED BY SNI

4.  Financing

     UNDER CURRENT TERMS AND CONDITIONS REPRESENTED BY THE EXISTING MASTER LEASE
     AGREEMENT IN PLACE BETWEEN EMC AND  SNI FUTURE SCHEDULES MAY BE ADDED AT
     THE THEN CURRENT COMPETITIVE RATES AND TERMS.

     THESE FINANCE RATES AND TERMS ALONG WITH THE LINE OF CREDIT PROVIDED TO SNI
     WILL BE REVIEWED BY EMC/SNI ON A MONTHLY/QUARTERLY BASIS BY APPROPRIATE
     PERSONNEL FROM BOTH ORGANIZATIONS. EMC WILL VALIDATE SNI'S CREDIT LINE ON A
     MONTHLY BASIS, NO LATER THAN THE FIRST DAY OF EACH MONTH AND WILL PROVIDE
     ANY UPATE INFORMATION TO SNI'S CFO, CONTROLLER OR OTHER APPROPRIATE
     PERSONNEL EMPLOYED BY SNI.

5.  No Solicitation Clause:

     SNI agrees that it will not, during the term of this Addendum, and for a
     period of six months after the date of termination, cancellation or
     expiration of this Addendum , hire nor solicit the employment in any
     capacity whatsoever of any employees of EMC, unless otherwise mutually
     agreed to by both parties.

6.  Termination of Purchase Commitments:

     Provided that SNI has purchased and paid for at least $[**] of EMC
     products, and with thirty days prior written notice, SNI may terminate this
     Addendum if EMC sells "shared storage."  Shared storage is a product
     offering of EMC (that is separate and distinct from the shared storage
     products and services currently and hereafter offered by the EMC Internet
     Services Group) that utilizes EMC storage products on a non-exclusive
     basis.

7.  Operational Considerations:

     EMC TECHNOLOGY ADVANCEMENTS: SNI MAY PARTAKE IN ALL EMC BETA PROGRAMS AS
     ANNOUNCED AND AS APPLICABLE.

 .    EMC AGREES THAT UPON GENERAL RELEASE OF VIRTUALIZATION FUNCTIONALITY, ALL
     EXISTING SYMMETRIX' PURCHASED BY SNI WILL BE PROVIDED THE VIRTUALIZATION
     UPGRADE SOFTWARE AT NO ADDITIONAL COST TO SNI. EMC ALSO AGREES THAT SNI
     WILL BE A MAJOR PART OF ALL BETA TESTING OF VIRTUALIZATION SOFTWARE
     FUNCTIONALITY


     PARTITIONING OF THE SYMMETRIX: "VIRTUALIZATION" - SYMMETRIX ACCESS CONTROL
     IS BEING IMPLEMENTED IN THE FOLLOWING PHASES:


 .    AT END OF [**], IF EMC HAS NOT PROVIDED VIRTUALIZATION FUNCTIONALITY AS
     DESCRIBED IN PHASE I, SNI MAY ELECT TO TERMINATE THIS ADDENDUM.

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Confidential Materials omitted and filed separately with the Securities and
                Exchange Commission. Asterisks denote omissions.

 .    IF AT THE BEGINNING OF [**], EMC HAS NOT PROVIDED VIRTUALIZATION
     FUNCTIONALITY AS DESCRIBED IN PHASE II, SNI MAY ELECT TO TERMINATE THIS
     ADDENDUM.

     .    Phase 1: Available [**]. Permits user configurable system call
          blocking by Symmetrix port. This feature has been implemented and has
          been patched back to micro-code level 65 This feature does not require
          changes to existing API's and applications Phase 1QA [**]and is
          approximately [**]% [**].

     .    Phase 2: Available ([**] Beta release to SNI) Permits creation of user
          defined groups of logical Symmetrix devices. This feature is a planned
          deliverable for micro-code level 67 This feature allows partitioned
          control of the Symmetrix per user defined device group For Example:
          TimeFinder and SRDF Control can be partitioned for multiple customers
          on the same Symmetrix To take advantage of this feature, changes must
          be made to existing API's and applications Phase 2 requirements [**],
          and [**].

 .  Demonstration Technology

      DEMONSTRATION SYMMETRIX FOR SNI: EMC AGREES TO PROVIDE SNI WITH A
      SYMMETRIX TO BE USED BY SNI SOLELY FOR DEMONSTRATION PURPOSES AT SNI
      CORPORATE, WALTHAM, MA - WITH THE FOLLOWING CONFIGURATION:

          SYMMETRIX 3930, 28 X 2020-36m2, 2 X DP2-USD4SW, 6 X DP2-FCD2, 2 X DP-
          RLD2'S, 6x50 METER CABLES, 8GB CACHE, CONTROL CENTER PACKAGE,
          TIMEFINDER OPEN AND NT, SRDF, VOLUME LOGIX

          EMC WILL AGREE TO DELIVER TO SNI H/Q WITHIN TWO WEEKS OF APPROVED AND
          EXECUTED ADDENDUM.

          DELIVERY TIMELINES: WITH CONSIGNMENT STRATEGY DEPLOYED, DELIVERY
          TIMELINE ISSUES WILL BE LARGELY REDUCED. FOR DELIVERY ISSUES NOT
          HANDLED BY CONSIGNMENT STRATEGY, EMC AGREES TO A 10 DAY TURN AROUND
          FOR  ALL HARDWARE AND SOFTWARE ITEMS.

          NOTE: THIS 10 DAY TURNAROUND IS REQUIRED TO ALLOW EMC TO ADDRESS AND
          RESPOND TO ANY SHORT INVENTORY ISSUES, AS WELL AS NORMAL ALLOCATION,
          TESTING AND PREPARATION PROCESSES EMC REQUIRES ON ANY PRODUCT TO BE
          SHIPPED.

          EMC WILL PROVIDE ONE POINT OF CONTACT FOR DELIVERY INFORMATION:   TBD
          EMC WILL PROVIDE ONE POINT OF CONTACT FOR PS PAYMENT AND   TRACKING:
          TBD
          EMC TO ASSIGN DEDICATED APPLICATION TECHNOLOGIES AND SYSTEMS ENGINEER
          TO SNI:
          APPLICATION TECHNOLOGIST: LOLIT VOHRA, EMC - NEWTON, MA SYSTEMS
          ENGINEER: TBD

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                Exchange Commission. Asterisks denote omissions.


 .  Software Development and Evaluation Technology

          EMC API FEES AND RUNTIME LICENSE FEES TO BE FURTHER DISCUSSED AND
          REVIEWED BY BOTH PARITIES PRIOR TO RESTRUCTURING PRESENT FORMAT
          ENGINEERING:
          .    EMC EVALUATION EQUIPMENT TO BE PROVIDED TO SNI AT NO CHARGE WITH
               EMC APPROVAL. UPON APPROVAL AND EXECUTION OF THIS ADDENDUM EMC
               WILL SHIP [**] WORTH OF EVAL EQUIPMENT. THE REMAINING PORTION OF
               EVALUATION EQUIPMENT TO BE PROVIDED TO SNI WILL SHIP
               PROPORTIONATELY AGAINST 50 MILLION DOLLARS
          .    EVALUATION EQUIPMENT IS NOT TO EXCEED AT ANY ONE TIME A TOTAL
               VALUE, TO BE CALCULATED USING THE VOLUME PURCHASE ADDENDUM
               DISCOUNTING STRUCTURE, OF $[**] OR [**]% OF THE TOTAL SNI
               PURCHASES FROM EMC DURING THE YEAR 2000, WHICH EVER IS LESSER.
          .    EMC ACT BETA TEST PROGRAM WILL CONTINUE TO BE MADE AVAILABLE TO
               SNI

  8.  Sales and Marketing Partnership

  The parties will engage in the following sales and marketing activities.  The
  specific implementation of the following activities will be approved by Tom
  Heiser or Mike Ruffolo. EMC reserves the right to delay or defer one or more
  of the sales and marketing activities set forth below due to any pending or
  contemplated offering of securities by SNI.

     INTERNAL AND EXTERNAL ANNOUNCEMENTS

     INTERNAL: WITH SNI INPUT, EMC WILL GENERATE AN ATTACK PACK TO BE
     DISTRIBUTED TO ENTIRE EMC FIELD. ATTACK PACK TO INCLUDE INFORMATION
     NECESSARY FOR EMC FIELD TO UNDERSTAND ALL RELATIVE BENEFITS PERTAINING TO
     THE SNI PARTNERSHIP:
     .    VALUE STATEMENT - OVERVIEW OF SNI'S MANAGED SERVICE MODEL AND STRENGTH
          IN THE INDUSTRY
     .    SUCCESS STORIES (CO GENERATED)
     .    MUTUAL RULES OF ENGAGEMENT
     .    PROCESS AND OPERATIONS (MUTUAL AGREEMENT ON STEPS IN THE SALES CYCLE,
          FROM INCEPTION TO CONCLUSION FOR BOTH COMPANIES). METHOD FOR
          DETERMINING ACCOUNTS WHICH WILL BENEFIT FROM JOINT ACTIVITIES WILL BE
          DETERMINED.
     .    QUESTION/ANSWER SECTION DESIGNED TO ADDRESS EMC FIELD REVENUE CREDIT
          AND COMPENSATION QUESTIONS EMC AND \SNI WILL GENERATE AND INVOLVE EMC
          IN A SIMILAR SNI ATTACK PACK TO BE CREATED AND DISTRIBUTED TO ENTIRE
          SNI FIELD
     .    INTERNET - EXTERNAL: EMC.COM TO ANNOUNCE EMC/SNI PARTNERSHIP AND
          PROVIDE A HYPERLINK TO THE SNI WEB SITE
     .    INTERNET - EXTERNAL: STORAGENETWORKS.COM TO ANNOUNCE SNI/EMC
          PARTNERSHIP AND PROVIDE A HYPERLINK TO EMC WEB SITE
     .    PRESS RELEASES FOR SHARED END USER CUSTOMERS WILL INCLUDE BOTH
          COMPANIES NAMES
     .    EMC WILL EXECUTE A PRESS RELEASE ANNOUNCING SNI AS EMC'S TIER ONE
          CHANNEL PROVIDER AND PROFESSIONAL SERVICES PROVIDER OF CHOICE.

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     .    SNI WILL EXECUTE A PRESS RELEASE ANNOUNCING EMC AS TECHNOLOGY PROVIDER
          OF CHOICE TO ADDRESS SERVICE LEVEL AGREEMENTS

     EMC SANCTIONED TRAINING SCHEDULE

     .    TRAINING EVENT TO INCLUDE: EMC AREA MEETING WHERE SNI AND EMC
          INTRODUCE OR RE INTRODUCE THE EMC/SNI PARTNERSHIP, SNI'S VALUE
          PROPOSITION, STRENGTH IN THE INDUSTRY, TARGET MARKET AND OVERALL
          BENEFIT OF PARTNERSHIP
     .    CITIES TO INCLUDE: SEATTLE, SAN FRANCISCO, LOS ANGELES, CHICAGO,
          DENVER, WASHINGTON DC, ATLANTA, NEW YORK, PHILADELPHIA, BOSTON,
          HOUSTON, AUSTIN, DALLAS, LONDON, FRANKFURT
     .    WEEKLY/MONTHLY AND QUARTERLY FIELD SALES VISITS TARGETED TO ASSIST
          EMC/SNI JOINT SALES EFFORTS IN SPECIFIC ACCOUNT OPPORTUNITIES.
     .    EMC MARKETING TO COORDINATE WITH SNI MARKETING TO CO CREATE AND CO
          DELIVER JOINT PRESS RELEASE TO MEDIA (E.G.. EMC PROVEN PROGRAM)
     .    EMC SEMINAR SERIES TO CONTINUE INTO 2000 WITH 2 SERIES, 6-12 CITIES
          EACH SERIES
     .    JOINT ADVERTISING PROGRAM COSTS TO BE EQUALLY SHARED AS DESCRIBED IN
          EMC'S MARKETING CO OP PROGRAM
     .    SNI WILL HAVE THE OPTION OF PARTICIPATING AT EMC SCHEDULED TRADE SHOW
          EVENTS
     .    COOP DOLLARS OR MARKET DEVELOPMENT FUNDS PROGRAM TO CONTINUE

9.  Term

  The term of this Addendum will be from February 2, 2000 through December 31,
  2000.


Authorized Signature: StorageNetworks, Inc.    Authorized Signature: EMC
Corporation

_________________________          ___________________________
Name                               Name
_________________________          ___________________________
Print                              Print
_________________________          ___________________________
Title                              Title
_________________________          ___________________________
Date                               Date

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