FORCE10 NETWORKS, INC. WARRANT TO PURCHASE SERIES E PREFERRED STOCK

Exhibit 10.14

THIS WARRANT AND THE SECURITIES ISSUABLE UPON THE EXERCISE HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. THEY MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED, HYPOTHECATED, OR OTHERWISE TRANSFERRED EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933, AS AMENDED OR AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT OR UNLESS SOLD PURSUANT TO RULE 144 UNDER SUCH ACT.

FORCE10 NETWORKS, INC.

WARRANT TO PURCHASE SERIES E PREFERRED STOCK

This Warrant is issued to                                                                   (“Holder”) by Force10 Networks, Inc., a Delaware corporation (the “Company”), on                                  (the “Warrant Issue Date”).

1. Purchase Shares. Subject to the terms and conditions hereinafter set forth, the Holder is entitled, upon surrender of this Warrant at the principal office of the Company (or at such other place as the Company shall notify the holder hereof in writing), to purchase from the Company up to one thousand eight hundred twenty-five (          ) fully paid and nonassessable shares of Series E Preferred Stock of the Company, as constituted on the Warrant Issue Date (the “Preferred Stock”). The number of shares of Preferred Stock issuable pursuant to this Section 1 (the “Shares”) shall be subject to adjustment pursuant to Section 8 hereof.

2. Exercise Price. The purchase price for the Shares shall be $           per share, as adjusted from time to time pursuant to Section 8 hereof (the “Exercise Price”).

3. Exercise Period. This Warrant shall be exercisable, in whole or in part, during the term commencing on the Warrant Issue Date and ending at 5:00 p.m. on                              provided, however, that in the event of (a) the closing of the issuance and sale of shares of Common Stock of the Company in the Company’s first underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended (the “IPO”), (b) the closing of the Company’s sale or transfer of all or substantially all of its assets, or (c) the closing of the acquisition of the Company by another entity by means of merger, consolidation or other transaction or series of related transactions, resulting in the exchange of the outstanding shares of the Company’s capital stock such that the stockholders of the Company prior to such transaction own, directly or indirectly, less than 50% of the voting power of the surviving entity, this Warrant shall, on the date of such event, no longer be exercisable and become null and void. In the event of a proposed transaction of the kind described above, the Company shall notify the holder of the Warrant at least fifteen (15) days prior to the consummation of such event or transaction.

4. Method of Exercise. While this Warrant remains outstanding and, exercisable in accordance with Section 3 above, the Holder may exercise, in whole or in part, the purchase rights evidenced hereby, Such exercise shall be effected by:

(a) the surrender of the Warrant, together with a duly executed copy of the form of Notice of Election attached hereto, to the Secretary of the Company at its principal offices; and

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(b) the payment to the Company of an amount equal to the aggregate Exercise Price for the number of Shares being purchased.

5. Net Exercise. In lieu of exercising this Warrant pursuant to Section 4, the Holder may elect to receive, without the payment by the Holder of any additional consideration, shares of Preferred Stock equal to the value of this Warrant (or the portion thereof being canceled) by surrender of this Warrant at the principal office of the Company together with notice of such election, in which event the Company shall issue to the holder hereof a number of shares of Preferred Stock computed using the following formula:

For purposes of this Section 5, the fair market value of one share of Preferred Stock (or, to the extent all such Preferred Stock has been converted into the Company’s Common Stock, the fair market value of one share of Common Stock) as of a particular date shall be determined as follows: (i) if traded on a securities exchange or through the Nasdaq National Market, the value shall be deemed to be the average of the closing prices of the securities on such exchange over the thirty (30) day period ending three (3) days prior to the net exercise election; (ii) if traded over-the-counter, the value shall be deemed to be the average of the closing bid or sale prices (whichever is applicable) over the thirty (30) day period ending three (3) days prior to the net exercise; and (iii) if there is no active public market, the value shall be the fair market value thereof, as determined in good faith by the Board of Directors of the Company; provided, that, if the Warrant is being exercised upon the closing of the IPO, the value will be the initial “Price to Public” of one share of such Preferred Stock (or Common Stock issuable upon conversion of such Preferred Stock) specified in the final prospectus with respect to such offering.

6. Certificates for Shares. Upon the exercise of the purchase rights evidenced by this Warrant, one or more certificates for the number of Shares so purchased shall be issued as soon as practicable thereafter (with appropriate restrictive legends, if applicable), and in any event within thirty (30) days of the delivery of the subscription notice.

7. Issuance of Shares. The Company covenants that the Shares, when issued pursuant to the exercise of this Warrant, will be duly and validly issued, fully paid and nonassessable and free from all taxes, liens, and charges with respect to the issuance thereof.

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8. Adjustment of Exercise Price and Number of Shares. The number of and kind of securities purchasable upon exercise of this Warrant and the Exercise Price shall be subject to adjustment from time to time as follows:

(a) Subdivisions, Combinations and Other Issuances. If the Company shall at any time prior to the expiration of this Warrant subdivide its Preferred Stock, by split-up or otherwise, or combine its Preferred Stock, or issue additional shares of its Preferred Stock or Common Stock as a dividend with respect to any shares of its Preferred Stock, the number of Shares issuable on the exercise of this Warrant shall forthwith be proportionately increased in the case of a subdivision or stock dividend, or proportionately decreased in the case of a combination. Appropriate adjustments shall also be made to the purchase price payable per share, but the aggregate purchase price payable for the total number of Shares purchasable under this Warrant (as adjusted) shall remain the same. Any adjustment under this Section 8(a) shall become effective at the close of business on the date the subdivision or combination becomes effective, or as of the record date of such dividend, or in the event that no record date is fixed, upon the making of such dividend.

(b) Reclassification, Reorganization and Consolidation. In case of any reclassification, capital reorganization, or change in the Preferred Stock of the Company (other than as a result of a subdivision, combination, or stock dividend provided for in Section 8(a) above), then, as a condition of such reclassification, reorganization, or change, lawful provision shall be made, and duly executed documents evidencing the same from the Company or its successor shall be delivered to the Holder, so that the Holder shall have the right at any time prior to the expiration of this Warrant to purchase, at a total price equal to that payable upon the exercise of this Warrant, the kind and amount of shares of stock and other securities and property receivable in connection with such reclassification, reorganization, or change by a holder of the same number of shares of Preferred Stock as were purchasable by the Holder immediately prior to such reclassification, reorganization, or change. In any such case appropriate provisions shall be made with respect to the rights and interest of the Holder so that the provisions hereof shall thereafter be applicable with respect to any shares of stock or other securities and property deliverable upon exercise hereof, and appropriate adjustments shall be made to the purchase price per share payable hereunder, provided the aggregate purchase price shall remain the same.

(c) Notice of Adjustment. When any adjustment is required to be made in the number or kind of shares purchasable upon exercise of the Warrant, or in the Warrant Price, the Company shall promptly notify the holder of such event and of the number of shares of Preferred Stock or other securities or property thereafter purchasable upon exercise of this Warrant.

9. Representations of Holder. With respect to this Warrant, Holder represents and warrants to the Company as follows:

(a) Experience. It is experienced in evaluating and investing in companies engaged in businesses similar to that of the Company; it understands that investment in the Warrant involves substantial risks; it has made detailed inquiries concerning the Company, its business and services, its officers and its personnel; the officers of the Company have made available to Holder any and all written information it has requested; the officers of the Company have answered to

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Holder’s satisfaction all inquiries made by it; in making this investment it has relied upon information made available to it by the Company; and it has such knowledge and experience in financial and business matters that it is capable of evaluating the merits and risks of investment in the Company and it is able to bear the economic risk of that investment.

(b) Investment. It is acquiring the Warrant for investment for its own account and not with a view to, or for resale in connection with, any distribution thereof. It understands that the Warrant, the shares of Preferred Stock issuable upon exercise thereof and the shares of Common Stock issuable upon conversion of the Preferred Stock, have not been registered under the Securities Act of 1933, as amended, nor qualified under applicable state securities laws.

(c) Rule 144. It acknowledges that the Warrant, the Preferred Stock and the Common Stock must be held indefinitely unless they are subsequently registered under the Securities Act or an exemption from such registration is available. It has been advised or is aware of the provisions of Rule 144 promulgated under the Securities Act.

(d) Access to Data. It has had an opportunity to discuss the Company’s business, management and financial affairs with the Company’s management and has had the opportunity to inspect the Company’s facilities.

10. No Fractional Shares or Scrip. No fractional shares or scrip representing fractional shares shall be issued upon the exercise of this Warrant, but in lieu of such fractional shares the Company shall make a cash payment therefor on the basis of the Exercise Price then in effect.

11. No Stockholder Rights. Prior to exercise of this Warrant, the Holder shall not be entitled to any rights of a stockholder with respect to the Shares, including (without limitation) the right to vote such Shares, receive dividends or other distributions thereon, exercise preemptive rights or be notified of stockholder meetings, and such holder shall not be entitled to any notice or other communication concerning the business or affairs of the Company. However, nothing in this Section 11 shall limit the right of the Holder to be provided the Notices required under this Warrant.

12. Transfers of Warrant. Subject to compliance with applicable federal and state securities laws, this Warrant and all rights hereunder are transferable in whole or in part by the Holder to any person or entity upon written notice to the Company. The transfer shall be recorded on the books of the Company upon the surrender of this Warrant, properly endorsed, to the Company at its principal offices, and the payment to the Company of all transfer taxes and other governmental charges imposed on such transfer. In the event of a partial transfer, the Company shall issue to the holders one or more appropriate new warrants.

13. Successors and Assigns. The terms and provisions of this Warrant and the Purchase Agreement shall inure to the benefit of, and be binding upon, the Company and the Holders hereof and their respective successors and assigns.

14. Amendments and Waivers. Any term of this Warrant may be amended and the observance of any term of this Warrant may be waived (either generally or in a particular instance and either retroactively or prospectively), with the written consent of the Company and the Holder.

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15. Market Stand-Off. Each Holder agrees in connection with the Company’s initial public offering of the Company’s securities, upon request of the Company or the underwriters managing any underwritten offering of the Company’s securities, not to sell, make any short sale of, loan, grant any option for the purchase of, or otherwise dispose of any Registrable Securities (other than those included in the registration) without the prior written consent of the Company or such underwriters, as the case may be, for such period of time (not to exceed one hundred eighty (180) days) from the effective date of such registration as may be requested by the underwriters. Each Holder further agrees to enter into a separate agreement providing for the foregoing, as may be required by the underwriters.

16. Notices. All notices required under this Warrant shall be deemed to have been given or made for all purposes (i) upon personal delivery, (ii) upon confirmation receipt that the communication was successfully sent to the applicable number if sent by facsimile; (iii) one day after being sent, when sent by professional overnight courier service, or (iv) five days after posting when sent by registered or certified mail. Notices to the Company shall be sent to the principal office of the Company (or at such other place as the Company shall notify the Holder hereof in writing). Notices to the Holder shall be sent to the address of the Holder on the books of the Company (or at such other place as the Holder shall notify the Company hereof in writing).

17. Attorneys’ Fees. If any action of law or equity is necessary to enforce or interpret the terms of this Warrant, the prevailing party shall be entitled to its reasonable attorneys’ fees, costs and disbursements in addition to any other relief to which it may be entitled.

18. Captions. The section and subsection headings of this Warrant are inserted for convenience only and shall not constitute a part of this Warrant in construing or interpreting any provision hereof.

19. Governing Law. This Warrant shall be governed by the laws of the State of California as applied to agreements among California residents made and to be performed entirely within the State of California.

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IN WITNESS WHEREOF, the parties hereto have caused this Warrant to be executed by an officer thereunto duly authorized.

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NOTICE OF EXERCISE

To: FORCE10 NETWORKS

The undersigned hereby represents and warrants that the undersigned is acquiring such shares for its own account for investment purposes only, and not for resale or with a view to distribution of such shares or any part thereof.

Date:                     

Name in which shares should be registered:

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