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                      FIRST AMENDMENT OF RIGHTS AGREEMENT


        THIS AMENDMENT (the "Amendment") dated November 21, 2000, to the Rights
Agreement (the "Rights Agreement") dated as of July 24, 1998 by and between
Computer Network Technology Corporation, a Minnesota corporation (the
"Company"), and ChaseMellon Shareholder Services, L.L.C., a New Jersey limited
liability company (the "Rights Agent").

                                  WITNESSETH:

        WHEREAS, the Company and the Rights Agent entered into the Rights
Agreement; and

        WHEREAS, on November 20, 2000, the Board of Directors of the Company, in
accordance with sections 27 and 28 of the Rights Agreement, determined it
desirable and in the best interests of the Company and its shareholders to amend
certain provisions of the Rights Agreement.

        NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein set forth, the parties hereby agree as follows:

        1.     AMENDMENT TO PARAGRAPH 7(B). Paragraph 7(b) of the Rights
Agreement is hereby amended and restated as follows:

        "The Purchase Price for each one-one-thousandth of a Preferred Share
        purchasable pursuant to the exercise of a Right shall be $100, and shall
        be subject to adjustment from time to time as provided in section 11 or
        13 hereof, and shall be payable in lawful money of the United States of
        America in accordance with paragraph (c) below."

        2.     AMENDMENT TO SECTION 7. Section 7 of the  Rights  Agreement is
amended by adding the following new paragraph (g) to the end of such section:

                      "(g) The Company shall use its best efforts to (i) file,
        as soon as practicable following the earliest date after a Person
        becomes an Acquiring Person and after the consideration to be delivered
        by the Company upon exercise of the Rights has been determined in
        accordance with Section 11(a)(iii) hereof, a registration statement
        under the Act (as defined in subparagraph 13(c)(i)), with respect to the
        securities purchasable upon exercise of the Rights on an appropriate
        form, (ii) cause such registration statement to become effective as soon
        as practicable after such filing, and (iii) cause such registration
        statement to remain effective (with a prospectus at all times meeting
        the requirements of the Act) until the earlier of (A) the date as of
        which the Rights are no longer exercisable for such securities, and (B)
        the date of the expiration of the Rights. The Company will also take
        such action as may be appropriate under, or to ensure compliance with,
        the securities or "blue sky" laws of the various states in connection
        with the exercisability of the Rights. The Company may temporarily
        suspend, for a period
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        of time not to exceed ninety (90) days after the date set forth in
        clause (i) of the first sentence of this section 7(g), the
        exercisability of the Rights in order to prepare and file such
        registration statement and permit it to become effective. Upon any such
        suspension, the Company shall issue a public announcement stating that
        the exercisability of the Rights has been temporarily suspended, as well
        as a public announcement at such time as the suspension has been
        rescinded (with prompt written notice of each such announcement to be
        given to the Rights Agent). In addition, if the Company shall determine
        that a registration statement is required following the Distribution
        Date, the Company may temporarily suspend (with prompt written notice
        thereof to the Rights Agent) the exercisability of the Rights until such
        time as a registration statement has been declared effective.
        Notwithstanding any provision of this Agreement to the contrary, the
        Rights shall not be exercisable in any jurisdiction if the requisite
        qualification in such jurisdiction shall not have been obtained, the
        exercise thereof shall not be permitted under applicable law, or a
        registration statement shall not have been declared effective."

        3.     AMENDMENT TO SECTION 26. The address for the Company stated in
section 26 of the Rights Agreement is hereby amended and restated to read as
follows:

                    "Computer Network Technology Corporation
                      6000 Nathan Lane North
                      Plymouth, Minnesota 55442
                      Attention:  President"

        4.     AMENDMENT TO EXHIBIT B. The first paragraph of Exhibit B of the
Rights Agreement is hereby amended to replace the use of the purchase price of
"$50" with "$100."

        5.     AMENDMENT TO EXHIBIT C. The first paragraph of Exhibit C of the
Rights Agreement is hereby amended to replace the use of the purchase price of
"$50" with "$100."

        6.     CONTINUING EFFECT. The Rights Agreement, except as amended
hereby, shall be and remain in full force and effect.

        7.     COUNTERPARTS. This Amendment may be executed in any number of
counterparts and each of such counterparts shall for all purposes be deemed an
original, and all such counterparts shall together constitute but one and the
same instrument. Signature pages delivered by facsimile shall be binding to the
same extent as an original.


                           [Signatures On Next Page.]


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        IN WITNESS WHEREOF, the parties have caused this Amendment to be
executed as of the day and year first above written.


                                        COMPUTER NETWORK TECHNOLOGY
                                        CORPORATION


                                        By /s/ Gregory T. Barnum
                                           ----------------------------------
                                           Name:Gregory T. Barnum
                                           Title: Chief Financial Officer and
                                           Secretary


                                        CHASEMELLON SHAREHOLDER
                                        SERVICES, L.L.C.


                                        By /s/ Georg Drake
                                           ----------------------------------
                                           Name:Georg Drake
                                           Title: Assistant Vice President


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