Exhibit 10.156



LOGO

3039 E CORNWALLIS RD

RESEARCH TRIANGLE PARK NC 27709-2195

October 1, 2009

Mr. Mike Harrison

Brocade Communications
Systems, Inc.

1745 Technology Drive

San Jose, CA 95110

Subject: Amendment 3 to SOW#8 of the IBM/Brocade Goods Agreement ROC-P-68

This letter (the Amendment) serves as Amendment Number 3 to SOW#8, including all amendments thereto (SOW#8) of the Goods
Agreement ROC-P-68 (the Agreement), which the parties hereto do mutually agree to amend as follows

1. Delete Attachment A,
Pricing in its entirety and replace with the attached Attachment A, Pricing.

2. The effective date of this Amendment shall be the date on the
top of this Amendment (the Effective Date).

The parties acknowledge that they have read this Amendment, understand it, and agree
to be bound by its terms and conditions. All capitalized terms not defined herein shall have the meaning set forth in the Goods Agreement or the SOW #8. All other terms and conditions of the Goods Agreement and SOW#8 that are unaffected by the
revisions set forth in this Amendment shall remain in full force and effect. Further, the parties agree that this Amendment and the Goods Agreement and SOW#8 are the complete and exclusive statement of the agreement between the parties, superseding
all proposals or other prior agreement, oral or written, and all other communications between the parties relating to this subject.



|                                            |  |                                      |  |         |  |                        |  |                      |  |        
|------------------------------------------- |  | ------------------------------------ |  | ------- |  | ---------------------- |  | -------------------- |  | -------
|Accepted and Agreed To:                     |  | Accepted and Agreed To:             
|                                            | 
|International Business Machines Corporation |  | Brocade Communications Systems, Inc.
|By:                                         |  | /s/ Michelle B. Wright               |  | 10/2/09 |  | By:                    |  | /s/ Matt Taylor      |  | 10/2/09
|                                            |  | Authorized Signature                 |  | Date    |  |                        |  | Authorized Signature |  | Date   
|                                            |  |                                      |  |        
|Michelle B. Wright                          |  |                                      |  |         |  | Matt Taylor            |  |                     
|Type or Print Name                          |  |                                      |  |         |  | Type or Print Name     |  |                     
|                                            |  |                                      |  |        
|GCM  Storage OEM Procurement               |  |                                      |  |         |  | Sr. Dir., OEM Services |  |                     
|Title & Organization                        |  |                                      |  |         |  | Title & Organization   |  |                     



|         |  |  |  |          |  |                      
|-------- |  |  |  | -------- |  | ---------------------
|Address: |  |  |  | Address: |  | 1745 Technology Drive
|         |  |  |  |          |  | San Jose, CA 95110   

IBM Brocade/Confidential



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Accepted and Agreed To:Brocade Communications Switzerland, SarLBy:

/s/ U. Plechschmidt

02-October-2009Authorized Signature

DateUlrich PlechschmidtType or Print NameVice President EMEATitle & Organization


IBM Brocade/Confidential



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ATTACHMENT A

[**] Pages 3-38 have been omitted and filed separately with the Securities and Exchange Commission. Confidential treatment has been requested with respect to the omitted portions.

IBM Brocade/Confidential