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                                                                   EXHIBIT 10.21

                              CALDERA SYSTEMS, INC.

                                VOTING AGREEMENT

         THIS VOTING AGREEMENT (this "Agreement") is made as of December 30,
1999, between Caldera Systems, Inc., a Utah corporation (the "Company"), each of
the holders of Series A Preferred Stock (as defined below), and each of the
holders of Series B Preferred Stock (as defined below). Such holders are
sometimes referred to herein individually as a "Stockholder" and collectively as
the "Stockholders". Certain capitalized terms used herein are defined in Section
4 hereof.

         The Company and the Stockholders desire to enter into this Agreement
for the purposes, among others, of establishing the composition of the Company's
Board of Directors (the "Board"). The execution and delivery of this Agreement
is a condition to the purchase of Series B Preferred Stock by certain
Stockholders pursuant to a purchase agreement dated as of the date hereof (the
"Series B Purchase Agreement").

         NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties to this Agreement hereby agree as
follows:

         1.       BOARD OF DIRECTORS.

                  (a) From and after the date hereof and until the earlier of
(x) the six month anniversary of the date of this Agreement if the Company has
not completed a Qualified Public Offering (as defined in Section 4) by such date
or (y) when the provisions of this Section 1 cease to be effective, each holder
of Stockholder Shares shall vote all of its Stockholder Shares which are voting
shares and any other voting securities of the Company over which such holder has
voting control and shall take all other reasonably necessary or desirable
actions within its control (whether in its capacity as a stockholder, director,
member of a board committee or officer of the Company or otherwise, and
including, without limitation, attendance at meetings in person or by proxy for
purposes of obtaining a quorum and execution of written consents in lieu of
meetings), and the Company shall take all reasonably necessary or desirable
actions within its control (including, without limitation, calling special board
and stockholder meetings), so that:

                  (i) the authorized number of directors on the Board shall be
         established at nine (9) directors;

                  (ii) the following individuals shall be elected to the Board:

                           (A) two (2) representatives designated by the Series
                  A Preferred Stockholders, determined by a vote of the holders
                  of a majority of the Stockholder


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                  Shares held by all such Series A Preferred Stockholders (the
                  "Series A Directors"), which shall initially be Ray Noorda and
                  Ralph Yarro III;

                           (B) one (1) representative designated by Citrix
                  Systems, Inc. (the "Citrix Director"), which shall initially
                  be Edward Iacobucci;

                           (C) one (1) representative designated by Egan
                  Managed-Capital, L.P. (the "Egan Managed-Capital Director"),
                  which shall initially be John R. Egan;

                           (D) one (1) representative designated by Novell, Inc.
                  (the "Novell Director"), which shall initially be Carl
                  Ledbetter;

                           (E) one (1) representative designated by Sun
                  Microsystems, Inc. (the "Sun Director"), who remains to be
                  identified;

                           (F) the chief executive officer of the Company (the
                  "CEO Director"), which shall initially be Ransom H. Love;

                           (G) one (1) representative designated by MTI
                  Technology Corporation (the "MTI Director"), which shall
                  initially be Thomas Raimondi; and

                           (H) one (1) representative designated by all holders
                  of Stockholder Shares determined on the basis of a vote of a
                  majority of the Stockholder Shares held by all Stockholders,
                  provided that such representative is not a member of the
                  Company's management or an employee or officer of the Company
                  (the "Outside Director"), and provided further that such
                  Outside Director is experienced in and familiar with the
                  management of a publicly-traded software company;

                  (iii) the removal from the Board (with or without cause) of
         any representative designated hereunder pursuant to subsection (ii)
         above shall be at the written request of the parties so designating
         such representative, but only upon such written request and under no
         other circumstances (in each case, determined on the same basis as the
         identity of such representative was determined pursuant to the
         applicable provision of subsection (ii) above), provided that if any
         director elected pursuant to subsection (ii)(D) above ceases to be the
         chief executive officer of the Company, he shall be promptly removed as
         a director; and

                  (iv) in the event that any representative designated hereunder
         pursuant to subsection (ii) above ceases to serve as a member of the
         Board during his term of office, the resulting vacancy on the Board
         shall be filled by a representative designated pursuant to subsection
         (ii) above in accordance with the same clause of subsection (ii) above
         as such representative was originally designated.

                  (v) Immediately upon the date when any of Citrix Systems,
         Inc., Egan Managed-Capital, L.P., Novell, Inc. or Sun Microsystems,
         Inc. shall own less than 500,000 shares of the Series B Preferred Stock
         or Common Stock issued upon conversion of the


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         Series B Preferred Stock (other than due to reverse stock splits or
         other action of the Company), such entity will no longer be entitled to
         a representative on the Board as required by paragraph 1(a)(ii)(B),
         (C), (D) or (E) and such entity's representative on the Board shall be
         deemed to have resigned effective as of such date. The Board may, at
         the option of the Board, reduce the size of the Board by one director
         or, in the alternative, the vacancy may be filled pursuant to the
         provisions of paragraph 1(a)(ii)(H). It is the intention of the parties
         that the entities specified in subparagraph 1(a)(ii)(B), (C), (D) and
         (E) shall only be able to designate a director so long as they own
         500,000 shares or more of Series B Preferred Stock of the Company or
         Common Stock issued upon conversion of the Series B Preferred Stock and
         that the right to elect a director shall not apply once such entity
         ceases to own at least 500,000 shares of the Series B Preferred Stock
         of the Company or Common Stock issued upon conversion of the Series B
         Preferred Stock.

         (b) Commencing on the sixth month anniversary of the date of this
Agreement and continuing until the provisions of this Section 1 cease to be
effective, each holder of Stockholder Shares shall vote all of its Stockholder
Shares which are voting shares and any other voting securities of the Company
over which such Stockholder has voting control and shall take all other
reasonable and necessary or desirable actions within its control (whether in its
capacity as a Stockholder, director, member of a Board committee or officer of
the Company or otherwise, and including, without limitation, attendance at
meetings in person or by proxy, for purposes of obtaining a quorum and execution
of written consents in lieu of meetings), and the Company shall take all
reasonably necessary or desirable actions within its control (including, without
limitation, calling special board and stockholder meetings), so that:

                           (i) the authorized number of directors on the Board
                               shall be established at eleven (11) directors;

                           (iii) the following individuals shall be elected to
                                 the Board:

                           (A) four (4) representatives designated by the Series
                  A Preferred Stockholders, determined by a vote of the holders
                  of a majority of the Stockholder Shares held by all such
                  Series A Preferred Stockholders (the "Series A Directors");

                           (B) one (1) representative designated by Citrix
                  Systems, Inc. (the "Citrix Director"), which shall initially
                  be Edward Iacobucci;

                           (C) one (1) representative designated by Egan
                  Managed-Capital, L.P. (the "Egan Managed-Capital Director"),
                  which shall initially be John R. Egan;

                           (D) one (1) representative designated by Novell, Inc.
                  (the "Novell Director"), which shall initially be Carl
                  Ledbetter;

                           (E) one (1) representative designated by Sun
                  Microsystems, Inc.] (the "Sun Director");


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                           (F) the chief executive officer of the Company (the
                  "CEO Director"), which shall initially be Ransom H. Love;

                           (G) one (1) representative designated by MTI
                  Technology Corporation (the "MTI Director") which shall
                  initially be Thomas Raimondi; and

                           (H) one (1) representative designated by all holders
                  of Stockholder Shares determined on the basis of a vote of a
                  majority of the Stockholder Shares held by all Stockholders,
                  provided that such representative is not a member of the
                  Company's management or an employee or officer of the Company
                  (the "Outside Director"), and provided further that such
                  Outside Director is experienced in and familiar with the
                  management of a publicly-traded software company;

                  (iii) the removal from the Board (with or without cause) of
         any representative designated hereunder pursuant to subsection (ii)
         above shall be at the written request of the parties so designating
         such representative, but only upon such written request and under no
         other circumstances (in each case, determined on the same basis as the
         identity of such representative was determined pursuant to the
         applicable provision of subsection (ii) above), provided that if any
         director elected pursuant to subsection (ii)(D) above ceases to be the
         chief executive officer of the Company, he shall be promptly removed as
         a director; and

                  (iv) in the event that any representative designated hereunder
         pursuant to subsection (ii) above ceases to serve as a member of the
         Board during his term of office, the resulting vacancy on the Board
         shall be filled by a representative designated pursuant to subsection
         (ii) above in accordance with the same clause of subsection (ii) above
         as such representative was originally designated.

                  (vi) Immediately upon the date when any of Citrix Systems,
         Inc., Egan Managed-Capital, L.P., Novell, Inc. or Sun Microsystems,
         Inc. shall own less than 500,000 shares of the Series B Preferred Stock
         or Common Stock issued upon conversion of the Series B Preferred Stock
         (other than due to reverse stock splits or other action of the
         Company), such entity will no longer be entitled to a representative on
         the Board as required by paragraph 1(b)(ii)(B), (C), (D) or (E) and
         such entity's representative on the Board shall be deemed to have
         resigned effective as of such date. The Board may, at the option of the
         Board, reduce the size of the Board by one director or, in the
         alternative, the vacancy may be filled pursuant to the provisions of
         paragraph 1(b)(ii)(H). It is the intention of the parties that the
         entities specified in subparagraph 1(b)(ii)(B), (C), (D) and (E) shall
         only be able to designate a director so long as they own 500,000 shares
         or more of Series B Preferred Stock of the Company or Common Stock
         issued upon conversion of the Series B Preferred Stock and that the
         right to elect a director shall not apply once such entity ceases to
         own at least 500,000 shares of the Series B Preferred Stock of the
         Company or Common Stock issued upon conversion of the Series B
         Preferred Stock.

                  (c) The Company shall pay the reasonable out-of-pocket
expenses incurred by each director in connection with attending the meetings of
the Board and any committee thereof.

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                  (d) The provisions of this Section 1 shall terminate
automatically and be of no further force and effect upon the first to occur of
(i) the written agreement of the parties hereto to terminate this Section 1 or
(ii) a Qualified Public Offering (as defined in Section 4 hereof).

                  (e) If any party fails to designate a representative to fill a
directorship pursuant to the terms of this Section 1, the individual previously
holding such directorship shall be elected to such position, or if such
individual fails or declines to serve, the election of an individual to such
directorship shall be accomplished in accordance with the Company's Bylaws and
applicable law; provided that the Stockholders shall vote to remove such
individual if the party which failed to designate such directorship so directs.

         2. REPRESENTATIONS AND WARRANTIES. Each Stockholder represents and
warrants that (i) such Stockholder is the record owner of the number of shares
of Preferred Stock and Stockholder Shares set forth opposite its name on
Schedule A attached hereto, as applicable, (ii) this Agreement has been duly
authorized, executed and delivered by such Stockholder and constitutes the valid
and binding obligation of such Stockholder, enforceable in accordance with its
terms, and (iii) such Stockholder has not granted and is not a party to any
proxy, voting trust or other agreement which is inconsistent with, conflicts
with or violates any provision of this Agreement. No holder of Stockholder
Shares shall grant any proxy or become party to any voting trust or other
agreement which is inconsistent with, conflicts with or violates any provision
of this Agreement.

         3. TRANSFER. Prior to transferring any Stockholder Shares (other than a
Public Sale) to any Person, the transferring holder of Stockholder Shares shall
cause the prospective transferee to be bound by this Agreement and to execute
and deliver to the Company and the other holders of Stockholder Shares a
counterpart of this Agreement.

         4. DEFINITIONS.

         "Common Stock" means the Company's Common Stock, no par value per
share.

         "Person" means an individual, a partnership, a corporation, a limited
liability company, an association, a joint stock company, a trust, a joint
venture, an unincorporated organization and a governmental entity or any
department, agency or political subdivision thereof.

         "Preferred Stock" means the Company's Series A Preferred Stock and
Series B Preferred Stock.

         "Public Sale" means any sale of Stockholder Shares to the public
pursuant to an offering registered under the Securities Act or to the public
through a broker, dealer or market maker pursuant to the provisions of Rule 144
adopted under the Securities Act.

         "Qualified Public Offering" means the closing of a firm commitment
underwritten public offering pursuant to an effective registration statement
filed under the Securities Act, covering the

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offer and sale of Common Stock for the account of the Company at a price per
share equal to or greater than $8.00 and in which the aggregate public offering
price (before deduction of underwriters' discounts and qualifications) equals or
exceeds $25 million.

         "Securities Act" means the Securities Act of 1933, as amended from time
to time.

         "Series A Preferred Stock" means the Company's Series A Preferred
Stock, no par value per share.

         "Series B Preferred Stock" means the Company's Series B Preferred
Stock, no par value per share.

         "Securities Act" means the Securities Act of 1933, as amended from time
to time.

         "Stockholder Shares" means (i) any Common Stock issued or issuable
directly or indirectly upon conversion of the Preferred Stock and (ii) any
Common Stock issued or issuable with respect to the securities referred to in
clause (i) above by way of stock dividend or stock split or in connection with a
combination of shares, recapitalization, merger, consolidation or other
reorganization. For purposes of this Agreement, any Person who holds Preferred
Stock shall be deemed to be the holder of the Stockholder Shares issuable
directly or indirectly upon conversion of the Preferred Stock in connection with
the transfer thereof or otherwise and regardless of any restriction or
limitation on the conversion thereof. As to any particular Stockholder Shares,
such shares shall cease to be Stockholder Shares when they have been (a)
effectively registered under the Securities Act and disposed of in accordance
with the registration statement covering them or (b) distributed to the public
through a broker, dealer or market maker pursuant to Rule 144 under the
Securities Act (or any similar provision then in force).

         "Transfer" means any transfer, assignment, pledge or other disposition
(whether with or without consideration and whether voluntarily or involuntarily
or by operation of law) of any interest in Stockholder Shares.

         5. TRANSFERS IN VIOLATION OF AGREEMENT. Any Transfer or attempted
Transfer of any Stockholder Shares in violation of any provision of this
Agreement shall be void, and the Company shall not record such Transfer on its
books or treat any purported transferee of such Stockholder Shares as the owner
of such shares for any purpose.

         6. AMENDMENT AND WAIVER. Except as otherwise provided herein, no
modification, amendment or waiver of any provision of this Agreement shall be
effective against the Company or the Stockholders unless such modification,
amendment or waiver is approved in writing by the Company and the holders of the
Stockholder Shares. The failure of any party to enforce any of the provisions of
this Agreement shall in no way be construed as a waiver of such provisions and
shall not affect the right of such party thereafter to enforce each and every
provision of this Agreement in accordance with its terms.

         7. SEVERABILITY. Whenever possible, each provision of this Agreement
shall be

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interpreted in such manner as to be effective and valid under applicable law,
but if any provision of this Agreement is held to be invalid, illegal or
unenforceable in any respect under any applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability shall not affect
the validity, legality or enforceability of any other provision of this
Agreement in such jurisdiction affect the validity, legality or enforceability
of any provision in any other jurisdiction, but this Agreement shall be
reformed, construed and enforced in such jurisdiction as if such invalid,
illegal or unenforceable provision had never been contained herein.

         8. ENTIRE AGREEMENT. Except as otherwise expressly set forth herein,
this Agreement embodies the complete agreement and understanding among the
parties hereto with respect to the subject matter hereof and supersedes and
preempts any prior understandings, agreements or representations by or among the
parties, written or oral, which may have related to the subject matter hereof in
any way.

         9. SUCCESSORS AND ASSIGNS. Except as otherwise provided herein, this
Agreement shall bind and inure to the benefit of and be enforceable by the
Company and its successors and assigns and the Stockholders and any subsequent
holders of Stockholder Shares and the respective successors and assigns of each
of them, so long as they hold Stockholder Shares.

         10. COUNTERPARTS. This Agreement may be executed in multiple
counterparts, each of which shall be an original and all of which taken together
shall constitute one and the same agreement.

         11. REMEDIES. The Company and the holders of Stockholder Shares shall
be entitled to enforce their rights under this Agreement specifically, to
recover damages by reason of any breach of any provision of this Agreement and
to exercise all other rights existing in their favor. The parties hereto agree
and acknowledge that money damages would not be an adequate remedy for any
breach of the provisions of this Agreement and that the Company and any holder
of Stockholder Shares may in its sole discretion apply to any court of law or
equity of competent jurisdiction for specific performance and/or injunctive
relief (without posting a bond or other security) in order to enforce or prevent
any violation of the provisions of this Agreement.

         12. NOTICES. Any notice provided for in this Agreement shall be in
writing and shall be either personally delivered, or mailed first class mail
(postage prepaid) or sent by reputable overnight courier service (charges
prepaid) to the Company at the address set forth below and to any other
recipient at the address indicated on the schedules hereto and to any subsequent
holder of Stockholder Shares subject to this Agreement at such address as
indicated by the Company's records, or at such address or to the attention of
such other person as the recipient party has specified by prior written notice
to the sending party. Notices shall be deemed to have been given hereunder when
delivered personally, three days after deposit in the U.S. mail and one day
after deposit with a reputable overnight courier service. The Company's address
is:

                          Caldera Systems, Inc.
                          240 West Center Street
                          Orem, Utah 84057

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         13. GOVERNING LAW. The issues and questions concerning the
construction, validity, interpretation and enforceability of this Agreement and
the schedules hereto shall be governed by, and construed in accordance with, the
laws of the State of Utah, without giving effect to any choice of law or
conflict of law rules or provisions (whether of the State of Utah or any other
jurisdiction) that would cause the application of the laws of any jurisdiction
other than the State of Utah. In furtherance of the foregoing, the internal law
of the State of Utah shall control the interpretation and construction of this
Agreement (and all schedules hereto), even though under that jurisdiction's
choice of law or conflict of law analysis, the substantive law of same other
jurisdiction would ordinarily apply.

         14. DESCRIPTIVE HEADINGS. The descriptive headings of this Agreement
are inserted for convenience only and do not constitute a part of this
Agreement.

                                    * * * * *

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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement on
the day and year first above written.


                                     CALDERA SYSTEMS, INC.


                                     By:
                                        ----------------------------------------

                                     Its:
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