CONFIDENTIAL TREATMENT
[***] INDICATES THAT TEXT HAS BEEN OMITTED WHICH IS THE SUBJECT OF A
CONFIDENTIAL TREATMENT REQUEST. THIS TEXT HAS BEEN FILED SEPARATELY WITH THE
SEC.

                                                                   EXHIBIT 10.23

            COMMVAULT SYSTEMS AMENDED AND RESTATED RESELLER AGREEMENT

This Reseller Agreement is made as of the effective Date set forth below,
between CommVault Systems, 2 Crescent Place, Oceanport, New Jersey 07757
("CommVault") and Dell Inc, ("Reseller").

This agreement is entered effective as of April 6, 2005.

WHEREAS, CommVault is engaged in the business of providing data storage
products.

WHEREAS, Reseller is a provider of information management solutions who wishes
to purchase software products from CommVault for the purposes of resale with
other products or services to customer in accordance with valid purchase orders.

THEREFORE, the parties agree as follows:

         1.       Price: Reseller receives a [***] discount on the MSRP of the
                  SW. Reseller shall provide CommVault with an applicable tax
                  exemption certificate. Reseller has the unrestricted right to
                  determine the prices at which it resells any Product to its
                  customers. No CommVault representative has the authority to
                  suggest that Reseller charge a particular resale price for any
                  product.

         2.       Purchase Orders: Reseller shall place purchase orders for
                  software with CommVault through the Dell 3GFX order process.
                  CommVault will accept or reject orders directly through the
                  3GFX system.

         3.       Payment: CommVault will electronically invoice Reseller
                  through the 3DFX process and payment for Products, including
                  any authorized partial shipments, shall be due in [***] from
                  the date that Dell receives the invoice.

         4.       Rebate: CommVault will rebate the Reseller on select orders in
                  the amount of [***] of the net S&P Software (SW licensing
                  only). [***].

         5.       Timeframe: This agreement will be in force from Feb 1, 2005
                  through July 31, 2005. This agreement will be re-evaluated
                  after each Dell Fiscal quarter and any changes will be made in
                  writing and agreed to by both Dell and CommVault.

         6.       Territory: United States only.

         7.       All Products will be subject to CommVault's MSRP in effect as
                  of April 6, 2005.

This agreement is intended to supersede any previous reseller agreements between
Dell and CommVault.


                                                                          Page 1



(Continued from Page 1, CommVault Systems Reseller Agreement)

By signing below, the Reseller acknowledges that it has read, understands, and
agrees, to be bound by all terms and conditions of this Reseller Agreement (the
"Agreement").


Dell, Inc.        ("Reseller")                          CommVault Systems
------------------------------------                    ------------------------


/s/ Michael P. Owens                                    /s/ Warren H. Mondschein
------------------------------------                    ------------------------
Signature                                               Signature



Michael P. Owens                                        Warren H. Mondschein
------------------------------------                    ------------------------
Name                                                    Name



Sr. Mgr, SW Procurement                                 VP & General Counsel
------------------------------------                    ------------------------
Title                                                   Title



9/14/06                                                 9/14/06
------------------------------------                    ------------------------
Date                                                    Date


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