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                                                                   EXHIBIT 10.47

                           FIRST AMENDMENT OF LEASE


     This First Amendment of Lease ("Amendment") is entered into by and between
David A. Sabey and Sandra L. Sabey, Husband and Wife  ("Landlord"), as Landlord
and Exodus Communications, Inc, a Delaware corporation ("Tenant"), as Tenant,
under that certain Lease ("Lease"), dated December 4, 1998, between the parties
hereto.

                                R E C I T A L S
                                - - - - - - - -

     A.   Landlord and Tenant desire to expand the Premises to include the third
floor of the Building and to provide for certain other amendments to the Lease.

     B.   Except as may be expressly provided otherwise in this Amendment,
capitalized terms in this Amendment shall have the meaning given such terms in
the Lease.

     NOW, THEREFORE, Landlord and Tenant agree as follows:
 
1.   Amendments.
     ---------- 

          1.1  Section 1.3 of the Lease is amended and restated in its entirety
to read as follows:

          1.3  PREMISES.  The "Premises" shall mean the space consisting of
approximately 99,288 net rentable square feet located on the first, second and
third floors of the Building, including 6,195 square feet in the annex building
and the 710 non-rentable square foot loading dock, which are depicted on the
floor plan attached to this Lease as Exhibit B, subject to recalculation in
accordance with Section 2. The loading dock shall be free of Rent during the
Term of this Lease. Landlord shall deliver the annex building of 6,195 rentable
s.f., the loading dock and approximately 28,500 net rentable square feet of
office space/data center to Tenant on February 1, 1999. Landlord shall pay a
penalty of Five Thousand Dollars ($5,000) to Tenant for each day that it delays
delivery of at least 25,000 net rentable square feet of office space/data
center, subject to Tenant's timely approvals and decisions, after March 1, 1999.
Approximately 32,593 net rentable square feet of additional space shall be
delivered to Tenant on June 1, 1999 and the remaining approximately 32,000 net
rentable square feet located on the third floor of the Building shall be
delivered June 1, 2000. The Premises shall include the tenant improvements, if
any, described in Exhibit C.

          1.2  Section 1.4 of the Lease is amended and restated in its entirety
to read as follows:

          1.4  TENANT'S SHARE. "Tenant's Share" shall mean "Tenant's Share of
the Building" or "Tenant's Share of the Property," as applicable. "Tenant's

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Share of the Building" shall initially mean thirty-four and ninety-three one
hundredths percent (34.93%). "Tenant's Share of the Property" shall initially
mean fourteen and fifty-five one hundredths percent (14.55%). Commencing on the
earlier of June 1, 1999 or the date on which Tenant first occupies all or any
portion of the remaining 32,593 net rentable square feet of office space/data
center located on the second floor, "Tenant's Share of the Building" shall
automatically be increased to sixty-seven and seventy-eight one hundredths
percent (67.78%) and "Tenant's Share of the Property" shall be automatically
increased to twenty-eight and twenty-one one hundredths percent (28.21%). The
earlier of: (i) the date that Tenant occupies the third floor space for purposes
other than build-out or (ii) June 1, 2000, "Tenant's Share of the Building"
shall automatically be increased to one hundred percent (100%) and "Tenant's
Share of the Property" shall be automatically increased to forty-one and sixty-
three one hundredths percent (41.63%). "Tenant's Share of the Building" is
calculated by dividing the net rentable area of the Premises by the net rentable
area of the Building (approximately 99,288 net rentable square feet). "Tenant's
Share of the Property" is calculated by dividing the net rentable area of the
Premises by the net rentable area of the Property (approximately 238,540 net
rentable square feet). In the event the rentable area of the Premises or
Building is altered or recalculated in accordance with Section 2, Landlord shall
adjust Tenant's Share of the Building to properly reflect such event. Landlord's
adjustment of such Tenant's Share shall be final.

          1.3  Section 1.9 of the Lease is amended and restated in its entirety
to read as follows:

          1.9  BASE RENT. "Base Rent" from the Commencement Date through May 31,
1999 shall mean the net rentable square feet of the first floor multiplied by
$10.25 per square foot per year, based on 34,695 rentable square feet of
Premises (Twenty-nine Thousand Six Hundred Thirty-five and 31/100 Dollars
($29,635.31) per month). "Base Rent" from June 1, 1999 through May 31, 2001
shall mean 67,288 net rentable square feet of Premises multiplied by $10.25 per
square foot per year, (Fifty-seven Thousand Four Hundred Seventy-five and 17/100
Dollars ($57,475.17) per month). Notwithstanding the foregoing, the earlier of:
(i) the date Tenant occupies the third floor space for other than build-out or
(ii) June 1, 2000, "Base Rent" from such date through May 31, 2001 shall be
increased to include the net rentable square feet of 32,000 multiplied by $10.50
per square foot per year for an additional Twenty-eight Thousand and 00/100
Dollars ($28,000.00) per month. "Base Rent" from June 1, 2001 through May 31,
2004 shall mean the net rentable square feet of 67,288 multiplied by $11.25 per
square foot per year and the net rentable square feet of 32,000 multiplied by
$11.50 (Ninety-three Thousand Seven Hundred Forty-nine and 17/100 Dollars
($93,749.17) per month). "Base Rent" from June 1, 2004 through May 31, 2006
shall mean the net rentable square feet of 67,288 multiplied by $12.50 per
square foot per year and the net rentable square feet of 32,000 multiplied by
$12.75 per square foot per year (One Hundred-four Thousand Ninety-one and 67/100
Dollars ($104,091.67) per month). "Base Rent" from June 1, 2006 through May 31,
2009 shall mean the net rentable square feet of 67,288 multiplied by $13.50 per
square foot per year and the net rentable square feet of 32,000 multiplied by
$13.75 per square foot per year, (One Hundred-twelve Thousand Three Hundred
Ninety-five and 67/100 Dollars ($112,365.67)

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per month). Prior to the Commencement Date, the net rentable square feet shall
be recalculated in accordance with Section 2. Base Rent shall be payable as
provided in Section 4.

     1.4  Section 1.10 of the Lease is amended and restated in its entirety to
read as follows:

          1.10 EARLY OCCUPANCY. Tenant will be allowed to occupy any square
footage on the first and second floors of the Premises they feel is ready for
occupancy before the Commencement Date, or any square footage on the third floor
of the Premises before June 1, 2000. Early Occupancy shall mean any use of the
space not directly related to the installation of equipment or constructing the
Premises. "Base Rent" for space located on the first and second floors of the
Premises will be calculated by multiplying the actual occupied rentable square
feet by $10.25 per net rentable square foot and "Base Rent" for space located on
the third floor of the Premises will be calculated by multiplying the actual
occupied rentable square feet by $10.50 per net rentable square foot. Tenant
will be responsible for all "Additional Rent" as described in Section 8 on the
portion of the space that they occupy early.

          1.5  Section 15.1 of the Lease is amended by adding the following to
the end of such Section:

     Notwithstanding the foregoing, Landlord hereby grants Tenant the right to
sublease all or a portion of the 32,000 net rentable square feet of Premises
located on the third floor of the Building; however, if the Rent that Tenant
charges to a sublessee is more than the Base Rent Tenant is paying on such
subleased Premises under this Lease, Tenant agrees to share fifty percent (50%)
of such additional amount with Landlord, which amount shall be paid to Landlord
on a monthly basis as Additional Rent throughout the term of the sublease.

     2.   Entire Amendment.  This Amendment sets forth the entire agreement of
          ----------------                                                    
the parties with respect to the subject matter set forth herein and may not be
modified other than by an agreement in writing signed by the parties hereto or
their respective successors and interests.

     3.   Exhibit.  Exhibit B-3 is attached hereto and incorporated herein by
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this reference.

     4.   Acknowledgment.  The parties hereto each acknowledge that except as
          --------------                                                     
expressly modified by this Amendment, all the terms and conditions of the Lease
remain unchanged and are in full force and effect and enforceable in accordance
with their terms.  In the event of a conflict between the Lease and this
Amendment, the terms and provisions of this Amendment shall control.

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     DATED this 4th day of December, 1998.

                              TENANT:

                              EXODUS COMMUNICATIONS, INC.



                              By:   /s/ Richard Stolz
                                    ----------------------------

                              Its:  CFO and COO
                                    ----------------------------



                              LANDLORD:


                              SABEY CORPORATION, as agent for David A. and
                              Sandra L. Sabey

 

                              By:   /s/ Laurent D. Poole
                                    ----------------------------

                              Its:  Executive VP
                                    ----------------------------

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STATE OF WASHINGTON )
                    ) ss.
COUNTY OF KING      )


     On this 4th day of December, 1998, before me, the undersigned, a Notary
Public in and for the State of Washington, duly commissioned and sworn as such,
personally appeared Laurent D. Poole, to me known to be the Executive VP of
SABEY CORPORATION, the corporation that executed the within and foregoing
instrument as agent for David A. and Sandra L. Sabey, and acknowledged the said
instrument to be the free and voluntary act and deed of said corporation for the
uses and purposes therein mentioned, and on oath stated that he was authorized
to execute said instrument, and that the seal affixed is the corporate seal of
said corporation.


     WITNESS my hand and official seal the day and year in this certificate
first above written.

 
                
         /s/
------------------------------

                                    Printed Name:   Mary A. Hall
                                                 ------------------------------
                                    My commission expires:   12-19-01
                                                          ---------------------

STATE OF CALIFORNIA     )
                        ) ss.
COUNTY OF SANTA CLARA   )


     On this 1st day of December, 1998, before me, the undersigned, a Notary
Public in and for the State of California, duly commissioned and sworn as such,
personally appeared Richard S. Stolz to me known to be the COO/CFO of Exodus
Communications, Inc., the corporation that executed the within and foregoing
instrument, and acknowledged the said instrument to be the free and voluntary
act and deed of said corporation for the uses and purposes therein mentioned,
and on oath stated that he/she was authorized to execute said instrument, and
that the seal affixed is the corporate seal of said corporation.


     WITNESS my hand and official seal the day and year in this certificate
first above written.


                                         /s/
                                    -------------------------------------------
                                    Printed Name:   Mary L. Woods
                                                 ------------------------------

                                    My commission expires:   June 26, 2001
                                                          ---------------------

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