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                                                                     EXHIBIT 5.1


                               FAEGRE & BENSON LLP
                  2200 Norwest Center, 90 South Seventh Street
                        Minneapolis, Minnesota 55402-3901
                             Telephone 612-336-3000
                                Fax 612-336-3026

                                 March 24, 1997


Digi International Inc.
11001 Bren Road East
Minnetonka, Minnesota 55343

          In connection with the proposed registration under the Securities Act
of 1933, as amended, of shares of Common Stock of Digi International Inc., a
Delaware corporation (the "Company"), offered and to be offered pursuant to the
Digi International Inc. Stock Option Plan as Amended and Restated (the "Plan"),
we have examined the Company's Restated Certificate of Incorporation, its
Amended and Restated By-Laws, and such other documents, including the
Registration Statement on Form S-8, dated the date hereof, to be filed with the
Securities and Exchange Commission relating to such shares (the "Registration
Statement"), and have reviewed such matters of law as we have deemed necessary
for this opinion.  Accordingly, based upon the foregoing, we are of the opinion
that:

          1.   The Company is duly and validly organized and existing and in
good standing under the laws of the State of Delaware.

          2.   The Company has duly authorized the issuance of the shares of
Common Stock which may be issued pursuant to the Plan.

          3.   The shares which may be issued pursuant to the Plan will be, upon
issuance, validly issued and outstanding and fully paid and nonassessable.

          4.   All necessary corporate action has been taken by the Company to
adopt the Plan, and the Plan is a validly existing plan of the Company.

          We consent to the filing of this opinion as an exhibit to the
Registration Statement.

                                Very truly yours,



                                Faegre & Benson LLP
                                -----------------------------------------------
                                FAEGRE & BENSON LLP

