<PAGE>   1
[CHAPARRAL NETWORK STORAGE, INC. LOGO]                            EXHIBIT 10.30


                         COMMON STOCK PURCHASE AGREEMENT
                                (Option Exercise)

         This Common Stock Purchase Agreement (the "Agreement") is made as of
the ____ day of _________, 1999, by and between CHAPARRAL NETWORK STORAGE, INC.,
a Delaware corporation (the "Company"), __________________ ("Purchaser") and
_____________ or other designated escrow agent (as Escrow Agent under Section 4
of this Agreement).

        The parties agree as follows:

        1. Common Stock Purchase.

                  1.1 Purchase. Subject to the terms and conditions of this
        Agreement, the Company hereby agrees to sell to Purchaser, and
        Purchaser hereby agrees to purchase from the Company, on the Closing
        Date (as defined herein) ______________ shares of the Company's Common
        Stock (the "Shares"), at a price of $_________________ per share
        ("Original Issuance Price") and an aggregate purchase price of
        $_____________________. The term "Shares" refers to the purchased
        Shares, all securities or property received in replacement of Shares,
        all securities or property distributed with respect to Shares, in any
        case by way of stock dividends, splits or consolidations, or pursuant
        to any re-capitalization, consolidation, merger, reorganization, or the
        like.

                  1.2 Payment. The aggregate purchase price shall be paid by
        Purchaser by check or wire transfer of funds.

        2. Closing; Delivery

                  2.1 Closing. The purchase and sale of the Shares shall occur
        at a closing (the "Closing") to be held at the principal office of the
        Company simultaneously with the execution of this Agreement by the
        parties, or on such other date as they may agree (the "Closing Date").

                  2.2 Delivery. At the Closing, the Company will deliver to
        Purchaser a certificate representing the Shares to be purchased by him
        (which shall be issued in Purchaser's name) against payment of the
        purchase price therefor. The purchase price for the Shares shall be paid
        on the Closing Date by delivery of the consideration referenced in
        Section 1.2 above.

        3. Limitations on Transfer. In addition to any other limitation
        on transfer created by applicable securities laws, Purchaser shall not
        assign, encumber, or dispose of any interest in the Shares except as
        provided in this Section 3.

                  3.1 Right of First Refusal.

                           (a) In the event Purchaser or his transferee desires
                  (or is required) to sell or transfer in any manner any of the
                  Shares, Purchaser shall first offer such Shares for sale to
                  the Company upon the terms and conditions specified herein
                  ("Right of First Refusal") by delivering a notice (the
                  "Notice") to the Company stating

                                    (i)     his bona fide intention to sell or
                         otherwise transfer such Shares,

                                    (ii)    the number of such Shares to be
                         sold to otherwise transferred,

                                    (iii)   the price for which Purchaser
                         proposes to sell such Shares,

                                    (iv)    the name of the proposed buyer or
                         transferee, and

                                    (v)     all additional terms and conditions,
                         if any, of the proposed sale or transfer.

                                    Purchaser shall attach to the Notice a copy
                  of the written offer, if any, reflecting the terms and
                  conditions of the proposed sale or transfer of the Shares to
                  the third party. In the

                                  CONFIDENTIAL                      Page 1 of 10
<PAGE>   2

                  event of a transfer not involving a sale of the Shares for a
                  specific sum of money, or if, in the sole judgement of the
                  Company's Board of Directors, the proposed transfer does not
                  involve a price for the Shares negotiated by Purchaser and its
                  proposed buyer or transferee in a bona fide "arm's length
                  transaction", the price of the Shares shall be determined by
                  the Company's Board of Directors in the manner specified in
                  Section 3.3 below.

                           (b) Within sixty (60) days following receipt by the
                  Company of the Notice ("Acceptance Period"), the Company (or
                  is assignee) may elect to purchase all or a portion of the
                  Shares to which the Notice refers, at the price per Share and
                  on the same terms and conditions (or terms and conditions as
                  reasonably similar as possible) as set forth in the Notice, or
                  at the price per Share determined pursuant to Section 3.3 in
                  the event that the price of the Shares is to be determined by
                  the Company's Board of Directors under Section 3.1 (a).

                           (c) If the Company (or its assignee) elects to
                  purchase such Shares hereunder, it shall notify Purchaser, in
                  writing, of its intention to purchase such Shares hereunder
                  and either (1) set a date for the closing of the transaction
                  at a place specified by the Company not later than thirty (30)
                  days from the date of such notice, at which time the Company
                  (or its assignee) shall tender payment for the Shares, or (2)
                  include payment for the Shares with the Company's notice to
                  Purchaser. At such closing, the certificate(s) representing
                  the Shares so purchased shall be delivered to the Company and
                  canceled (and the Shares transferred to the Company's
                  assignee, if applicable) as of the date of the mailing of the
                  Company's notice and, thereafter, shall be promptly returned
                  by Purchaser to the Company by certified or registered mail.

                           (d) If the Company (or its assignee) does not elect
                  to purchase all of the Shares to which the Notice refers,
                  Purchaser may sell or otherwise transfer the Shares not
                  purchased to the third party named in the Notice at the price
                  and on the terms and conditions specified in the Notice, or at
                  a higher price; provided that such sale or transfer is
                  consummated within sixty (60) days from the earlier of

                                    (i)  the lapse of the Acceptance Period, or

                                    (ii) the date of the Company's notice,
                           whether written or oral, advising Purchaser that the
                           Company does not intend to purchase the Shares
                           hereunder; provided, further, that any such sale or
                           transfer is made in accordance with all of the terms
                           and conditions set forth in this Agreement.

                           In the event the Shares are not disposed of by
                  Purchaser within such sixty (60) day period, such Shares shall
                  once again be subject to the Right of First Refusal.

                  3.2 Involuntary Transfer.

                           (a) In the event of any transfer by operation of law
                  or other involuntary transfer, of all, or a portion, of the
                  Shares, the Company shall have an option to purchase all of
                  the Shares transferred (the "Involuntary Transfer Option") at
                  a price set pursuant to Section 3.3. Upon such a transfer, the
                  person acquiring the Shares shall promptly notify the
                  Secretary of the Company of such transfer.

                           (b) The Company (or its assignee) shall notify
                  Purchaser and the person acquiring the Shares as to whether
                  the Company (or its assignee) wishes to purchase the shares
                  pursuant to the Involuntary Transfer Option within forty-five
                  (45) days following the date on which the Company was notified
                  of the transfer. If the Company (or its assignee) elects to
                  purchase such Shares hereunder it shall set a date for the
                  closing of the transaction at a place specified by the Company
                  not later than thirty (30) days from the date of the Company's
                  notice to Purchaser and the person acquiring the Shares. At
                  such closing, the Company (or its assignee) shall tender
                  payment for the shares in the form of a check, cancellation of
                  Purchaser's indebtedness to the Company, or some combination
                  thereof, and the certificate(s) representing the Shares so
                  purchased shall be canceled.

                  3.3 Determination of Price by Board. With respect to the
         Shares to be transferred pursuant to the Right of First Refusal or the
         Involuntary Transfer Option where the price per Share is to be
         determined pursuant to this Section 3.3, the price per Share shall be
         a price set by the Board of Directors of the Company that is
         determined by the Board to reflect the then current value of such
         Shares. The


                                  CONFIDENTIAL                      Page 2 of 10

<PAGE>   3

         Company shall notify Purchaser, his representative, or the person
         acquiring the Shares under Section 3.2 of the price so determined
         within forty-five (45) days after receipt by the Company of written
         notice of the transfer or proposed transfer of the Shares.

                  3.4 Restriction on Alienation. Any sale, transfer, or
         disposition or purported sale, transfer, or disposition or any of the
         shares by Purchaser shall be null and void unless the terms,
         conditions, and provisions of this Agreement are strictly complied
         with. Purchaser hereby authorizes and directs the Transfer Agent of the
         Company to transfer the Shares as to which the Right of First Refusal
         or Involuntary Transfer Option has been exercised from Purchaser to the
         Company (or its assignee). Purchaser further authorizes the Company to
         refuse, or to cause its Transfer Agent to refuse, to transfer, or
         record any Shares to be transferred in violation of this Agreement.

                  3.5 Assignment by Company. The Company's Right of First
         Refusal, and Involuntary Transfer Option may be assigned, in whole or
         in part, to any shareholder or shareholders of the Company.

                  3.6 Obligations Binding Upon Transferees. All transferees of
         Shares or any interest therein will receive and hold such Shares or
         interests subject to the provisions of this Agreement, including,
         insofar as applicable, the Company's Right of First Refusal, and
         Involuntary Transfer Option under this Section 3. Any sale or transfer
         of the Shares shall be void unless the provisions of this Agreement are
         met.

                  3.7 Termination of Rights. The Right of First Refusal, and the
         Involuntary Transfer Option granted by this Section 3 shall terminate
         (a) on the occurrence of the merger or consolidation of the Company
         into, or the sale of all or substantially all of the Company's assets,
         to another entity, except that these restrictions on transfer shall not
         terminate if immediately after such merger, consolidation, or sale of
         assets, at least fifty-one percent (51%) of the capital stock of such
         other corporation is owned by persons who are holders of Shares of
         capital stock of the Company immediately before such merger,
         consolidation, or sale, or (b) at such time as a public market exists
         for the Company's Common Stock (or any other stock issued to purchasers
         in exchange for the Shares purchased under this Agreement). For the
         purpose of this Agreement, a "public market" shall be deemed to exist
         if the Common Stock is listed on a national securities exchange (as
         that term is used in the Securities Exchange Act of 1934), or the
         Common Stock is traded on the over-the-counter market and prices are
         published daily on business days in a recognized financial journal.

                  3.8 Replacement Certificate. In the event the restrictions
         imposed by this Agreement shall be terminated as provided in this
         Section 3, a new certificate or certificates representing the Shares
         shall be issued, on request, without the legend referred to in Section
         6.1 (b) herein.

                  3.9 Excluded Transfers. The restrictions on transfer of this
         Section 3 shall not apply to an inter-vivos transfer to Purchaser's
         ancestors or descendants or spouse or to a Trustee for their benefit,
         provided that such transferee shall take such Shares subject to all the
         terms of this Agreement, including restrictions on further transfer.

                  3.10 Indebtedness. Notwithstanding any provision to the
         contrary in this Agreement, any payment by the Company for purchase of
         Shares from Purchaser may be made by cancellation of any indebtedness
         to the Company from Purchaser.

                  3.11 Market Standoff Agreement. Purchaser, if requested by the
         Company and an underwriter of Common Stock (or other securities) of
         the Company, agrees not to sell or otherwise transfer or dispose of
         any Common Stock (or other securities) of the Company held by
         Purchaser during the period not to exceed one hundred and eighty (180)
         days as requested by the managing underwriter following the effective
         date of a registration statement of the Company filed under the
         Securities Act (as hereafter defined), provided that all officers and
         directors of the Company are required to enter into similar
         agreements. Such agreement shall be in writing in the form
         satisfactory to the Company and such underwriter. The Company may
         impose stop transfer instructions with respect to the shares (or other
         securities) subject to the foregoing restriction until the end of such
         period.

         4. Escrow; Escrow Instructions. As security for Purchaser's faithful
         performance of the terms and provisions of this Agreement, and to
         insure the availability for delivery of the Shares upon the Company's
         (or its assignee's) exercise of the Right of First Refusal, or
         Involuntary Transfer Option, Purchaser shall, at the Closing Date,
         deliver and deposit with _________________ or such other person
         designated by the Company


                                  CONFIDENTIAL                      Page 3 of 10

<PAGE>   4

         as Escrow Agent in this transaction, the share certificate(s)
         representing the Shares, together with a stock assignment duly
         endorsed in blank (in the form of Exhibit A to this Agreement). The
         Escrow Agent is hereby authorized and directed to hold the documents
         delivered to the Escrow Agent pursuant to the terms of this Agreement,
         including the stock certificate(s), evidencing the Shares and the
         stock assignment in accordance with the following terms of this
         Section 4.

                  4.1 Rights Exercise. In the event the Company (or its
         assignee) shall elect to exercise the Right of First Refusal, or
         Involuntary Transfer Option set forth in Section 3 of this Agreement
         (collectively the "Rights") in whole or in part, the Company (or its
         assignee) shall give to Purchaser and to Escrow Agent a written notice
         specifying a time, place, and/or manner for a closing hereunder.

                  4.2 Closing Instructions. Purchaser and the Company hereby
         irrevocably authorize and direct Escrow Agent to take all such actions
         as may be necessary or proper to close the transaction contemplated by
         such notice in accordance with the terms of such notice. At the
         closing, Escrow Agent is directed to

                           (a) date such stock assignment as shall be necessary
                  for the specific transfer,

                           (b) fill in the number of Shares being transferred,
                  and

                           (c) deliver the same, together with the
                  certificate(s) evidencing the Shares to be transferred, to the
                  Company (or its assignee) as provided in this Agreement
                  against the simultaneous delivery to Escrow Agent of the
                  purchase price for the number of Shares being purchased
                  pursuant to this Agreement.

                  4.3 Additional Share Deposit. Purchaser irrevocably authorizes
         the Company to deposit with Escrow Agent any securities (including
         additional shares of the Company's Common Stock) or other property
         (including cash) which Purchaser would be entitled to receive on
         account of any Shares held by Escrow Agent hereunder. To facilitate the
         performance of this Agreement, Purchaser irrevocably constitutes and
         appoints Escrow Agent as his attorney-in-fact and agent for the term of
         the escrow to execute with respect to such Shares all stock
         certificates, stock assignments, or other instruments, which shall be
         necessary or appropriate to make such securities negotiable and to
         complete any transaction contemplated under this Agreement, including
         but not limited to any filings to comply with state or federal
         securities laws.

                  4.4 Share Release. Upon written request from the Company and
         Purchaser, Escrow Agent is authorized to release from escrow the number
         of Shares indicted in that written request pursuant to this Agreement.

                  4.5 Escrow Termination. The escrow shall terminate upon the
         termination of the Company's Rights under Section 3 of this Agreement.
         Upon termination of this escrow, Escrow Agent shall deliver to
         Purchaser all documents, securities, or other property belonging to
         Purchaser that are still in Escrow Agent's possession, and Escrow Agent
         shall be discharged of all further obligations under Section 4.

                  4.6 Escrow Amendment. Escrow Agent's duties hereunder may be
         altered, amended, modified, or revoked only by a writing signed by all
         of the parties to this Agreement and approved by Escrow Agent.

                  4.7 Escrow Agent Liability. Escrow Agent shall not be
         personally liable for any act Escrow Agent may do or omit to do
         hereunder as Escrow Agent or attorney-in-fact for Purchaser while
         acting in good faith and in the exercise of Escrow Agent's own good
         judgement and any act done or omitted by Escrow Agent pursuant to the
         advice of Escrow Agent's own attorneys shall be conclusive evidence of
         such good faith. Escrow Agent shall not be liable in any respect on
         account of the identities, authorities, or rights of the parties
         executing or delivering or purporting to execute or deliver this
         Agreement or any documents or papers deposited or called for hereunder.
         Escrow Agent shall not be liable for the termination of any rights
         under any applicable statute of limitations with respect to the
         provisions of this Section 4 or any documents deposited with Escrow
         Agent.

                  4.8 Court Orders. Escrow Agent is hereby expressly authorized
         to disregard any and all warnings given by any of the parties hereto or
         by any other person or corporation, excepting only orders or process of
         courts of law, and is hereby expressly authorized to comply with and
         obey orders, judgements, or decrees of any court. In case Escrow Agent
         obeys or complies with any such order,

                                  CONFIDENTIAL                      Page 4 of 10


<PAGE>   5



         judgement, or decree of any court, Escrow Agent shall not be liable to
         any of the parties hereto or to any other person, firm, or corporation
         by reason of such compliance, notwithstanding that any such order,
         judgement, or decree shall be subsequently reversed, modified,
         annulled, set aside, vacated, or found to have been entered without
         jurisdiction.

                  4.9 Execution Effect. By signing this Agreement, the Escrow
         Agent becomes a party hereto only for the purpose of Section 4. and
         for no other provisions of this Agreement.

                  4.10 Escrow Agent Successors. If, prior to the termination of
         this Escrow, ____________ shall die or shall cease to be Escrow Agent
         of the Company, any other officer of the Company may, from time to
         time, at the request of the Company's Board of Directors, discharge any
         of the duties and perform any of the acts to be performed by
         __________________ as Escrow Agent.

         5. Investment Representations. In connection with the
         acquisition of the Shares, Purchaser represents to the Company the
         following:

                  5.1 Investment. Purchaser is acquiring the Shares to be issued
         to Purchaser for investment for Purchaser's own account and not with
         the view to, or for resale in connection with, any distribution,
         assignment, or resale within the meaning of the Securities Act of 1933
         (the "Securities Act"), or the Delaware Corporate Securities Law, as
         amended ("Delaware Securities Law") to others and no other person has a
         direct or indirect beneficial interest, in whole or in part, in such
         Shares. Purchaser understands that the Shares to be issued to Purchaser
         have not been and will not be registered under the Securities Act or
         qualified under the Delaware Securities Law, or under the laws of any
         other state of the United States in reliance upon specific exemptions
         therefrom which depend upon, among other things, the bona fide nature
         of the investment intent as expressed herein, and in any other
         representations, warranties, or information provided by Purchaser to
         the Company under this Agreement.

                  5.2 Restrictions on Transfer. Purchaser acknowledges that the
         Shares to be issued to Purchaser must be held indefinitely unless
         subsequently registered and qualified under the Securities Act, or
         unless an exemption from registration and qualification is otherwise
         available. Purchaser further understands that the Company is under no
         obligation to register or qualify the Shares.

                  5.3 Rule 144. Purchaser is aware of the provisions of Rule
         144, promulgated under the Securities Act, which permits limited public
         resale of "restricted securities" acquired, directly or indirectly,
         from the issuer thereof (or from an affiliate of such issuer), in a
         non-public offering subject to the satisfaction of certain conditions.

                  5.4 Exemption from Registration. Purchaser further
         acknowledges that, in the event all of the applicable requirements of
         Rule 144 are not satisfied, registration under the Securities Act,
         compliance with Regulation A, or some other registration exemption will
         be required.

                  5.5 Relationship to Company; Experience. Purchaser either has
         a preexisting business or personal relationship with the Company or any
         of its officers, directors, or controlling persons or, by reason of
         Purchaser's business or financial experience, has the capacity to
         protect Purchaser's own interests in connection with Purchaser's
         acquisition of the Shares to be issued to Purchaser hereunder.
         Purchaser has such knowledge and experience in financial, tax, and
         business matters to enable Purchaser to utilize the information made
         available to Purchaser in connection with the acquisition of the Shares
         to evaluate the merits and risks of the prospective investment and to
         make an informed investment decision with respect thereto.

                  5.6 Purchaser's Liquidity. In reaching the decision to invest
         in the Shares, Purchaser has carefully evaluated Purchaser's financial
         resources and investment position and the risks associated with this
         investment, and Purchaser acknowledges that Purchaser is able to bear
         the economic risks of the investment. Purchaser

                           (a) has adequate means of providing for
                  Purchaser's current needs and possible personal contingencies,

                           (b) has no need for liquidity in Purchaser's
                  investment,

                           (c) is able to bear the substantial economic
                  risks of an investment in the Shares for an indefinite period,
                  and

                                  CONFIDENTIAL                      Page 5 of 10

<PAGE>   6



                           (d) at the present time, can afford a complete loss
                  of such investment. Purchaser's commitment to investments
                  which are not readily marketable is not disproportionate to
                  Purchaser's net worth, and Purchasers investment in the Shares
                  will not cause Purchaser's overall commitment to become
                  excessive.

                  5.7 Offer and Sale. Purchaser understands that the offer and
         sale of the Shares have not been registered under the Securities Act in
         reliance upon exemption therefrom. Purchaser was not offered or sold
         the Shares, directly or indirectly, by means of any form of general
         solicitation or general advertisement, including the following:

                           (a) any advertisement, article, notice, or other
                  communication published in any newspaper, magazine, or
                  similar medium, or broadcast over television or radio; or

                           (b) any seminar or meeting whose attendees had been
                  invited by general solicitation or general advertising.

                  5.8 Access to Data. Purchaser is aware of the Company's
         business affairs and financial condition, and has acquired sufficient
         information about the Company to reach an informed and knowledgeable
         decision to acquire the Shares. Purchaser acknowledges that during the
         course of this transaction and before deciding to acquire the Shares,
         Purchaser has been provided with financial and other written
         information about the Company. Purchaser has been given the opportunity
         by the Company to obtain any information and ask questions concerning
         the Company, the Shares, and Purchaser's investment that Purchaser felt
         necessary; and to the extent Purchaser availed himself of that
         opportunity, Purchaser has received satisfactory information and
         answers.

                  5.9 Risks. Purchaser acknowledges and understands that

                           (a) any investment in the Company constitutes a high
                  risk,

                           (b) the Shares are highly speculative, and

                           (c) there can be no assurance as to what return, if
                  any, there may be.

                            Purchaser is aware that the Company may issue
         additional securities in the future which could result in the dilution
         of Purchaser's ownership interest in the Company.

                  5.10 Valid Agreement. This Agreement, when executed and
         delivered by Purchaser, shall constitute a valid and legally binding
         obligation of Purchaser which is enforceable in accordance with its
         terms.

                  5.11 Residence. The address set forth on the signature page of
         this Agreement is Purchaser's current address and accurately sets forth
         Purchaser's place of residence.

         6. Securities Compliance.

                  6.1 Legends. The certificate or certificates representing the
         Shares shall bear legends in substantially the following form (in
         addition to any other legend imposed by applicable blue sky laws or the
         Articles or Bylaws of the Company):

                                    (a) THE SHARES REPRESENTED BY THIS
                  CERTIFICATE HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A
                  VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION
                  THEREOF. NO SUCH SALE OR DISPOSITION MAY BE EFFECTED WITHOUT
                  AN EFFECTIVE REGISTRATION STATEMENT RELATED THERETO, OR AN
                  OPINION OF COUNSEL FOR THE COMPANY THAT SUCH REGISTRATION IS
                  NOT REQUIRED UNDER THE SECURITIES ACT OF 1993.

                                    (b) THE SHARES REPRESENTED BY THIS
                  CERTIFICATE ARE SUBJECT TO TRANSFER RESTRICTIONS IN ACCORDANCE
                  WITH THE TERMS OF AN AGREEMENT BETWEEN THE COMPANY AND THE
                  SHAREHOLDER, A COPY OF WHICH IS ON FILE WITH THE SECRETARY OF
                  THE COMPANY.

                                    (c) THE SECURITIES EVIDENCED BY THIS
                  CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT
                  OF 1933, AS AMENDED, AND MAY NOT BE SOLD, TRANSFERRED,
                  ASSIGNED OR HYPOTHECATED UNLESS THERE IS AN


                                  CONFIDENTIAL                      Page 6 of 10

<PAGE>   7



                  EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT COVERING SUCH
                  SECURITIES, THE SALE IS MADE IN ACCORDANCE WITH RULE 144 OR
                  RULE 701 UNDER SUCH ACT, OR THE COMPANY RECEIVES AN OPINION OF
                  COUNSEL FOR THE HOLDER OF THESE SECURITIES REASONABLY
                  SATISFACTORY TO THE COMPANY, STATING THAT SUCH SALE, TRANSFER,
                  ASSIGNMENT OR HYPOTHECATION IS EXEMPT FROM THE REGISTRATION
                  AND PROSPECTUS DELIVERY REQUIREMENTS OF SUCH ACT.

                  6.2 No Qualification. THE SALE OF THE SECURITIES WHICH ARE THE
         SUBJECT OF THIS AGREEMENT, IF NOT YET QUALIFIED WITH THE DELAWARE
         CORPORATION COMMISSIONER, IS SUBJECT TO SUCH QUALIFICATION OR AN
         EXEMPTION BEING AVAILABLE, AND THE ISSUANCE OF SUCH SECURITIES, OR THE
         RECEIPT OF ANY PART OF THE CONSIDERATION PRIOR TO SUCH QUALIFICATION IS
         UNLAWFUL. THE RIGHTS OF THE PARTIES TO THIS AGREEMENT ARE EXPRESSLY
         CONDITIONED UPON SUCH QUALIFICATION BEING OBTAINED OR AN EXEMPTION
         BEING AVAILABLE.

                  6.3 Transfers. In addition to the restrictions imposed under
         Section 3, all transfers of Shares or any interest in any such Shares
         shall be made in strict compliance with applicable state and federal
         securities laws and the Articles and Bylaws of the Company.

         7. Tax Considerations. Purchaser understands that the tax consequences
         to the Purchaser as a result of this transaction depend on Purchaser's
         individual circumstances and the characterization of this transaction.
         Further, Purchaser will be responsible for any personal tax liability,
         whether federal, state, or local, as a result of this transaction and
         Purchaser's ownership of the Shares. Purchaser has consulted with
         Purchaser's own advisor(s) with respect to this transaction and has not
         relied on any advice from the Company or any of its officers,
         directors, agents, or representations.

         8. Miscellaneous.

                  8.1 Amendment. This Agreement may only be amended by written
         agreement between Company and Purchaser (or, with respect to Section 4,
         by written agreement among the Company, Purchaser, and the Escrow
         Agent).

                  8.2 Notices. Any notice, demand, request, or other
         communications hereunder shall be deemed sufficient when delivered
         personally or sent by courier or upon deposit in the United State mail,
         as certified, registered, or first class mail, with postage prepaid,
         and addressed, if to the Company, at it principal place of business,
         Attention: the President, if to Purchaser, at his address as shown on
         the stock records of the Company, or if to Escrow Agent, at
         ________________________. The address to which notice is to be given
         hereunder may be changed from time to time by the parties entitled to
         notice by notice given to all other parties as provided herein.

                  8.3 Successors and Assigns. The rights and benefits of this
         Agreement shall inure to the benefit of, and be enforceable by, the
         Company's successors and assigns. The rights and obligations of
         Purchaser under this Agreement may only be assigned with the prior
         written consent of the Company.

                  8.4 Further Actions. Both parties agree to execute any
         additional documents and take such further action as may be reasonably
         necessary to carry out the purposes of this Agreement.

                  8.5 Shareholder Rights. Subject to the provisions of this
         Agreement, Purchaser shall, during this term of this Agreement,
         exercise all rights and privileges of a shareholder of the Company
         with respect to the shares.

                  8.6 Injunctive Relief. Purchaser agrees that the Company
         and/or other shareholders shall be entitled to a decree of specific
         performance of the terms hereof or an injunction restraining violations
         of this Agreement, such right to be in addition to any of the remedies
         of the Company. No remedy provided herein is intended to be exclusive
         of any other remedy, and each and every remedy shall be cumulative and
         shall be in addition to every other remedy given hereunder, or now or
         hereafter existing at law or in equity.

                  8.7 Governing Law. This Agreement shall be governed by and
         construed in accordance with the laws of the State of Colorado, other
         than the conflict of laws and except for matters of corporate
         governance which shall be governed by and construed according to the
         laws of the State of Delaware.

                                  CONFIDENTIAL                      Page 7 of 10

<PAGE>   8


                  8.8 Severability. If any provision of this Agreement is held
         by a court of competent jurisdiction to be invalid, void, or
         unenforceable, the remaining provisions shall nevertheless continue in
         full force and effect without being impaired or invalidated in any way
         and shall be construed in accordance with the purposes, tenor, and
         effect of this Agreement.

                  8.9 No Employment Effect. Nothing contained herein shall
         confer upon Purchaser any right to continue in the employ of, or
         consulting relationship with, the Company, and the Company reserves all
         rights to discharge Purchaser for any reason whatsoever, with or
         without cause.

                  8.10 Expenses. Each party hereto shall pay his own expenses
         incurred (including, with limitation, the fees of counsel) on his
         behalf in connection with this Agreement or any transactions
         contemplated by this Agreement.

                  8.11 Entire Agreement. This Agreement embodies the entire
         agreement and understanding of the parties hereto in respect of the
         subject matter hereof and supersedes all prior and contemporaneous
         written or oral communications or agreements between the Company and
         Purchaser regarding the subject matter hereof, and no amendment or
         addition hereto shall be deemed effective unless agreed to, in writing,
         by the parties hereto.

                  8.12 Waivers. No waiver of any provision of this Agreement or
         any rights or obligations of any party hereunder shall be effective,
         except pursuant to a written instrument signed by the party or parties
         waiving compliance, and any such waiver shall be effective only in the
         specific instance and for the specific purpose stated in such writing.

                  8.13 Counterparts. This Agreement may be executed in one or
         more counterparts each of which shall be an original and all of which
         together shall constitute one and the same instrument.

                  8.14 Attorneys' Fees. If any legal action or any arbitration
         or other proceeding is brought for the enforcement of this Agreement,
         or because of an alleged dispute, breach, default, or misrepresentation
         in connection with any provision of this Agreement, the successful or
         prevailing party shall be entitled to recover reasonable attorneys'
         fees and other costs incurred in that action or proceeding, in addition
         to any other relief to which it may be entitled.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first set forth above.

CHAPARRAL NETWORK STORAGE, INC.                      PURCHASER



---------------------------------------              ---------------------------
Gary L.. Allison, Chairman & CEO                     Purchaser
1951 South Fordham Street                            Street
Longmont, CO 80503                                   City, State, Zip

For purposes of Section 4 only:

Escrow Agent



---------------------------------------

                                  CONFIDENTIAL                      Page 8 of 10

<PAGE>   9





                                SPOUSE'S CONSENT

         I acknowledge that I have read the foregoing Common Stock Purchase
Agreement and that I know its content. I am aware that by its provisions my
spouse agrees to sell all his or her shares, including any community property
interest I may have, on the occurrence of certain events. I hereby consent to
the sale, approve the provisions of the Agreement, and agree that these Shares
and any interest I may have in them are subject to the provisions of the Common
Stock Purchase Agreement and that I will take no action at any time to hinder
the operation of the Common Stock Purchase Agreement on these Shares or any
interest I may have in them.



Spouse of Purchaser





Signature                                     Date
          ---------------------------------         ----------------------------
          Spouse



                                    EXHIBIT A

                      ASSIGNMENT SEPARATE FROM CERTIFICATE

FOR VALUE RECEIVED ____________ hereby sells, assigns, and transfers unto
CHAPARRAL NETWORK STORAGE, INC. (__________) shares of the Common Stock (the
"Shares") of CHAPARRAL NETWORK STORAGE, INC., a Delaware corporation (the
"Company"), standing in the undersigned's name on the books of the Company
represented by Certificate No. ________ herewith, and does hereby irrevocably
constitute and appoint __________________________________________ attorney to
transfer such Shares on the books of the Company with full power of substitution
in the premises.








Signature                                       Date
          -----------------------------------         --------------------------
          Purchaser

THIS ASSIGNMENT MAY ONLY BE USED IN CONNECTION WITH THE RIGHTS OF THE COMPANY
UNDER A COMMON STOCK PURCHASE AGREEMENT WITH THE SIGNATORY OF THIS ASSIGNMENT.


                                  CONFIDENTIAL                      Page 9 of 10


<PAGE>   10





                      STOCK CERTIFICATE AND ESCROW RECEIPT


         The undersigned Purchaser acknowledges receipt of a copy of Certificate
No. ____ for ___________ shares of Common Stock of CHAPARRAL NETWORK STORAGE,
INC.

         The undersigned understands that the original of the stock certificate
has been deposited into escrow in accordance with Section 4 of the Common Stock
Purchase Agreement, and is being held by the Escrow Agent at the principal
offices of CHAPARRAL NETWORK STORAGE, INC.

         The undersigned acknowledges that the certificate contains legends
restricting transfer as specified in Section 6 of the Common Stock Purchase
Agreement.





Signature                                   Date
          --------------------------------        ------------------------------
          Purchaser


                                  CONFIDENTIAL                     Page 10 of 10