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                                                                     Exhibit 3.1

                           CERTIFICATE OF AMENDMENT TO
                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                     OF BROCADE COMMUNICATIONS SYSTEMS, INC.


       Brocade Communications Systems, Inc., a corporation organized and
existing under and by virtue of the General Corporation Law of the State of
Delaware (the "Corporation"), DOES HEREBY CERTIFY:

       FIRST: That the Board of Directors of the Corporation approved a
resolution by unanimous written consent to amend Article IV of the Amended and
Restated Certificate of Incorporation of the Corporation to read in its entirety
as follows:

                                   ARTICLE IV

              1. Authorized Capital. The Company is authorized to issue two
       classes of shares of stock to be designated, respectively, Common Stock,
       $.001 par value, and Preferred Stock, $0.001 par value. The total number
       of shares that the Company is authorized to issue is 805,000,000 shares.
       The number of shares of Common Stock authorized is 800,000,000. The
       number of shares of Preferred Stock authorized is 5,000,000. The
       Preferred Stock may be issued from time to time in one or more series
       pursuant to a resolution or resolutions providing for such issue duly
       adopted by the Board of Directors (authority to do so being hereby
       expressly vested in the Board). The Board of Directors is further
       authorized to determine or alter the rights, preferences, privileges and
       restrictions granted to or imposed upon any wholly unissued series of
       Preferred Stock and to fix the number of shares of any series of
       Preferred Stock and the designation of any such series of Preferred
       Stock. The Board of Directors, within the limits and restrictions stated
       in any resolution or resolutions of the Board of Directors originally
       fixing the number of shares constituting any series, may increase or
       decrease (but not below the number of shares in any such series then
       outstanding), the number of shares of any series subsequent to the issue
       of shares of that series.

       SECOND: The Annual Meeting of Stockholders of the Corporation was duly
called and held on April 4, 2001 in accordance with Section 222 of the General


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Corporation law of the State of Delaware at which meeting a majority of the
outstanding shares of the Corporation were voted in favor of the proposed
amendment.

       THIRD: That said amendment was duly adopted by the Board of Directors and
stockholders of the Corporation in accordance with the provisions of Section 242
of the General Corporation Law of the State of Delaware.

       IN WITNESS WHEREOF, the Corporation has caused this certificate to be
signed on its behalf by the undersigned duly authorized officer of the
Corporation on this 20th day of April, 2001.



                                        ----------------------------------------
                                        Michael J. Byrd
                                        Chief Financial Officer