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                                              CERTIFICATIONS

         I, John Rodriguez, certify that:

     1)   I have  reviewed  this annual report on Form 10-K/A of F5 Networks,
          Inc.

     2)   Based on my  knowledge,  this  report does not contain any untrue
          statement  of a material  fact or omit to state a  material  fact
          necessary  to  make  the   statements   made,  in  light  of  the
          circumstances   under  which  such   statements  were  made,  not
          misleading with respect to the period covered by this report;

     3)   Based  on my  knowledge,  the  financial  statements,  and  other
          financial  information included in this report, fairly present in all
          material  respects  the  financial  condition,   results  of
          operations  and cash flows of the  registrant as of, and for, the
          periods presented in this report;

     4)   The registrant's  other certifying  officer and I are responsible for
          establishing  and  maintaining   disclosure   controls  and procedures
          (as  defined  in  Exchange  Act Rules  13a-15(e)  and 15d-15(e))  and
          internal  control over  financial  reporting  (as defined in Exchange
          Act Rules  13a-15(f) and  15d-15(f))  for the registrant and have:

          a)   Designed such disclosure controls and procedures,  or caused such
               disclosure  controls  and  procedures  to be  designed  under our
               supervision,  to ensure that material information relating to the
               registrant,  including  its  consolidated  subsidiaries,  is made
               known to us by others within those entities,  particularly during
               the period in which this report is being prepared;

          b)   Designed  such  internal  control over  financial  reporting,  or
               caused such  internal  control  over  financial  reporting  to be
               designed under our supervision,  to provide reasonable  assurance
               regarding  the   reliability  of  financial   reporting  and  the
               preparation  of financial  statements  for  external  purposes in
               accordance with generally accepted accounting principles;

          c)   Evaluated  the  effectiveness  of  the  registrant's   disclosure
               controls  and   procedures  and  presented  in  this  report  our
               conclusions  about the  effectiveness of the disclosure  controls
               and  procedures,  as of the  end of the  period  covered  by this
               report based on such evaluation; and

          d)   Disclosed in this report any change in the registrant's  internal
               control  over  financial   reporting  that  occurred  during  the
               registrant's most recent fiscal quarter (the registrant's  fourth
               fiscal  quarter  in  the  case  of an  annual  report)  that  has
               materially  affected,  or  is  reasonably  likely  to  materially
               affect,   the   registrant's   internal  control  over  financial
               reporting; and

     5)   The registrant's  other certifying  officer and I have disclosed,
          based on our most  recent  evaluation  of internal  control  over
          financial reporting,  to the registrant's  auditors and the audit
          committee  of the  registrant's  board of  directors  (or persons
          performing the equivalent function):

          a)   All  significant  deficiencies  and  material  weaknesses  in the
               design or operation of internal control over financial reporting,
               which are reasonably  likely to adversely affect the registrant's
               ability  to  record,  process,  summarize  and  report  financial
               information; and

          b)   Any fraud,  whether or not material,  that involves management or
               other employees who have a significant  role in the  registrant's
               internal control over financial reporting.

    Date: April 3, 2007

                   /s/ JOHN RODRIGUEZ
                   ------------------
                   John Rodriguez
                   Senior Vice President, Chief Accounting Officer




