EXHIBIT 4.2

                            REGISTRATION RIGHTS AGREEMENT

    REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT"), dated as of May 22, 1997,
by and among Zitel Corporation, a California corporation, with headquarters
located at 47211 Bayside Parkway, Fremont, California 94538 (the "COMPANY"), and
each of the undersigned (together with their respective affiliates and any
assignee or transferee of all of their respective rights hereunder, the "INITIAL
INVESTORS"). 

    WHEREAS:

    A.   In connection with the Securities Purchase Agreement by and among the
parties hereto dated as of May 21, 1997 (the "SECURITIES PURCHASE AGREEMENT"),
the Company has agreed, upon the terms and subject to the conditions contained
therein, to issue and sell to the Initial Investors convertible subordinated
debentures (the "DEBENTURES") that are convertible into shares (the "CONVERSION
SHARES") of the Company's common stock (the "COMMON STOCK"), upon the terms and
subject to the limitations and conditions set forth in such Debentures; and

    B.   To induce the Initial Investors to execute and deliver the Securities
Purchase Agreement, the Company has agreed to provide certain registration
rights under the Securities Act of 1933, as amended, and the rules and
regulations thereunder, or any similar successor statute (collectively, the
"1933 ACT"), and applicable state securities laws;

    NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company and each of the
Initial Investors hereby agree as follows:

    1.   DEFINITIONS.

         a.   As used in this Agreement, the following terms shall have the
following meanings:

              (i)  "INVESTORS" means the Initial Investors and any transferee
or assignee who agrees to become bound by the provisions of this Agreement in
accordance with Section 9 hereof.

              (ii) "REGISTER," "REGISTERED," and "REGISTRATION" refer to a
registration effected by preparing and filing a Registration Statement or
Statements in compliance with the 1933 Act and pursuant to Rule 415 under the
1933 Act or any successor rule providing for offering securities on a continuous
basis ("RULE 415"), and the declaration or ordering of effectiveness of such
Registration Statement by the United States Securities and Exchange Commission
(the "SEC").


                                 Exhibit 4.2 - Page 1


              (iii)     "REGISTRABLE SECURITIES" means the Conversion Shares
issued or issuable and any shares of capital stock issued or issuable as a
dividend on or in exchange for or otherwise with respect to any of the foregoing
(including, but limited to, Common Stock issuable upon conversion of the
principal and interest of the Debentures or shares issuable pursuant to the
damage provisions of the Debentures and hereunder).

              (iv) "REGISTRATION STATEMENT" means a registration statement of
the Company under the 1933 Act.

         b.   Capitalized terms used herein and not otherwise defined herein
shall have the respective meanings set forth in the Securities Purchase
Agreement.

    2.   REGISTRATION.

         a.   MANDATORY REGISTRATION.  The Company shall prepare, and, on or
prior to the date which is forty-five (45) days after the date of the Closing
under the Securities Purchase Agreement (the "CLOSING DATE"), file with the SEC
a Registration Statement on Form S-3 (or, if Form S-3 is not then available, on
such form of Registration Statement as is then available to effect a
registration of the Registrable Securities, subject to the consent of the
Initial Investors, which consent will not be unreasonably withheld) covering the
resale of the Registrable Securities underlying the Debentures issued pursuant
to the Securities Purchase Agreement, which Registration Statement, to the
extent allowable under the 1933 Act and the Rules promulgated thereunder
(including Rule 416),  shall state that such Registration Statement also covers
such indeterminate number of additional shares of Common Stock as may become
issuable upon conversion of the Debentures (i) to prevent dilution resulting
from stock splits, stock dividends or similar transactions or (ii) by reason of
changes in the Conversion Price of the Debentures in accordance with the terms
thereof.  The number of shares of Common Stock initially included in such
Registration Statement shall be no less than two (2) times the number of
Conversion Shares that are then issuable upon conversion of the Debentures as of
the date of filing of the Registration Statement without regard to any
limitation on the Investor's ability to convert the Debentures.

         b.   UNDERWRITTEN OFFERING.  If any offering pursuant to a
Registration Statement pursuant to Section 2(a) hereof involves an underwritten
offering, the Investors who hold a majority in interest of the Registrable
Securities subject to such underwritten offering, with the consent of a
majority-in-interest of the Initial Investors, shall have the right to select
one legal counsel and an investment banker or bankers and manager or managers to
administer the offering, which investment banker or bankers or manager or
managers shall be reasonably satisfactory to the Company.

         c.   PAYMENTS BY THE COMPANY.  The Company shall use its best efforts
to obtain effectiveness of the Registration Statement as soon as practicable. 
If (i) the Registration Statement(s) covering the Registrable Securities
required to be filed by the Company pursuant to Section 2(a) hereof is not
declared effective by the SEC within ninety (90) days after the Closing Date or
if, after the 

                                 Exhibit 4.2 - Page 2


Registration Statement has been declared effective by the SEC, sales cannot be
made pursuant to the Registration Statement, or (ii) the Common Stock is not
listed or included for quotation on the Nasdaq National Market (the 
"NASDAQ-NMS"), the Nasdaq SmallCap Market ("NASDAQ SMALLCAP"), the New York 
Stock Exchange (the "NYSE") or the American Stock Exchange (the "AMEX") after 
being so listed or included for quotation, then the Company will make 
payments to the Investors in such amounts and at such times as shall be 
determined pursuant to this Section 2(c) as partial relief for the damages to 
the Investors by reason of any such delay in or reduction of their ability to 
sell the Registrable Securities (which remedy shall not be exclusive of any 
other remedies available at law or in equity).  The Company shall pay to each 
holder of the Debentures or Registerable Securities an amount equal to the 
then outstanding principal amount of the Debentures (and, in the case of 
holders of Registerable Securities, the principal amount of Debentures from 
which such Registerable Securities were converted) ("OUTSTANDING PRINCIPAL 
AMOUNT") multiplied by two hundredths (.020) times the sum of: (i) the number 
of months (prorated for partial months) after the end of such 90-day period 
and prior to the date the Registration Statement is declared effective by the 
SEC, provided, however, that there shall be excluded from such period any 
delays which are solely attributable to (A) changes required by the Investors 
in the Registration Statement with respect to information relating to the 
Investors, including, without limitation, changes to the plan of 
distribution, or to the failure of the Investors to conduct their review of 
the Registration Statement pursuant to Section 3(h) below in a reasonably 
prompt manner and (B) changes in the relevant policy, procedure, 
interpretation, position, practice or rule of the SEC announced after the 
Closing Date; (ii) the number of months (prorated for partial months) that 
sales cannot be made pursuant to the Registration Statement after the 
Registration Statement has been declared effective (excluding days during an 
Allowed Delay (as defined in Section 3(f) below)); and (iii) the number of 
months (prorated for partial months) that the Common Stock is not listed or 
included for quotation on the Nasdaq-NMS, Nasdaq SmallCap, NYSE or AMEX after 
the Registration Statement has been declared effective.  (For example, if the 
Registration Statement becomes effective one (1) month after the end of such 
90-day period, the Company would pay $20,000 for each $1,000,000 of 
Outstanding Principal Amount.  If thereafter, sales could not be made 
pursuant to the Registration Statement for an additional period of one (1) 
month, the Company would pay an additional $20,000 for each $1,000,000 of 
Outstanding Principal Amount.)  Such amounts shall be paid in cash or, at 
each Investor's option, may be added to the principal of the Debentures and 
thereafter be convertible into Common Stock at the "CONVERSION PRICE" (as 
defined in the Debentures) in accordance with the terms of the Debentures.  
Any shares of Common Stock issued upon conversion of such amounts shall be 
Registrable Securities.  If the Investor desires to convert the amounts due 
hereunder into Registrable Securities, it shall so notify the Company in 
writing within two (2) business days of the date on which such amounts are 
first payable in cash and such amounts shall be so convertible (pursuant to 
the mechanics set forth under Article I of the Debentures), beginning on the 
last day upon which the cash amount would otherwise be due in accordance with 
the following sentence. Payments of cash pursuant hereto shall be made within 
five (5) days after the end of each period that gives rise to such 
obligation, provided that, if any such period extends for more than thirty 
(30) days, interim payments shall be made for each such thirty (30) day 
period.

         d.   PIGGY-BACK REGISTRATIONS.  If at any time prior to the expiration
of the 

                                 Exhibit 4.2 - Page 3


Registration Period (as hereinafter defined) the Company shall file with the SEC
a Registration Statement relating to an offering for its own account or the
account of others under the 1933 Act of any of its equity securities (other than
on Form S-4 or Form S-8 or their then equivalents relating to equity securities
to be issued solely in connection with any acquisition of any entity or business
or equity securities issuable in connection with stock option or other employee
benefit plans), the Company shall send to each Investor who is entitled to
registration rights under this Section 2(d) written notice of such determination
and, if within fifteen (15) days after the effective date of such notice, such
Investor shall so request in writing, the Company shall include in such
Registration Statement all or any part of the Registrable Securities such
Investor requests to be registered, except that if, in connection with any
underwritten public offering for the account of the Company the managing
underwriter(s) thereof shall impose a limitation on the number of shares of
Common Stock which may be included in the Registration Statement because, in
such underwriter(s)' judgment, marketing or other factors dictate such
limitation is necessary to facilitate public distribution, then the Company
shall be obligated to include in such Registration Statement only such limited
portion of the Registrable Securities with respect to which such Investor has
requested inclusion hereunder as the underwriter shall permit. Any exclusion of
Registrable Securities shall be made pro rata among the Investors seeking to
include Registrable Securities in proportion to the number of Registrable
Securities sought to be included by such Investors; PROVIDED, HOWEVER, that the
Company shall not exclude any Registrable Securities unless the Company has
first excluded all outstanding securities, the holders of which are not entitled
to inclusion of such securities in such Registration Statement or are not
entitled to pro rata inclusion with the Registrable Securities; and PROVIDED,
FURTHER, HOWEVER, that, after giving effect to the immediately preceding
proviso, any exclusion of Registrable Securities shall be made pro rata with
holders of other securities having the right to include such securities in the
Registration Statement other than holders of securities entitled to inclusion of
their securities in such Registration Statement by reason of demand registration
rights.  No right to registration of Registrable Securities under this Section
2(d) shall be construed to limit any registration required under Section 2(a)
hereof.  If an offering in connection with which an Investor is entitled to
registration under this Section 2(d) is an underwritten offering, then each
Investor whose Registrable Securities are included in such Registration
Statement shall, unless otherwise agreed by the Company, offer and sell such
Registrable Securities in an underwritten offering using the same underwriter or
underwriters and, subject to the provisions of this Agreement, on the same terms
and conditions as other shares of Common Stock included in such underwritten
offering.

         e.   ELIGIBILITY FOR FORM S-3.  The Company represents and warrants
that it meets the registrant eligibility and transaction requirements for the
use of Form S-3 for registration of the sale by the Initial Investors and any
other Investors of the Registrable Securities and the Company shall file all
reports required to be filed by the Company with the SEC in a timely manner so
as to meet the "registrant eligibility" requirements in the general instructions
to Form S-3.  The Company further represents and warrants that it currently
meets the "registrant eligibility" requirements for primary issuances set forth
in the general instructions to Form S-3.



                                 Exhibit 4.2 - Page 4


    3.   OBLIGATIONS OF THE COMPANY.  

    In connection with the registration of the Registrable Securities, the
Company shall have the following obligations:

         a.   The Company shall prepare promptly, and file with the SEC not
later than forty-five (45) days after the Closing Date, a Registration Statement
with respect to the number of Registrable Securities provided in Section 2(a),
and thereafter use its best efforts to cause such Registration Statement
relating to Registrable Securities to become effective as soon as possible after
such filing, and keep the Registration Statement effective pursuant to Rule 415
at all times until such date as is the earlier of (i) the date on which no
Debentures are outstanding and all of the Registrable Securities have been sold
and (ii) the date on which the Registrable Securities (in the opinion of counsel
to the Initial Investors) may be immediately sold without registration or
limitation under Rule 144(k) (the "REGISTRATION PERIOD"), which Registration
Statement (including any amendments or supplements thereto and prospectuses
contained therein) shall not contain any untrue statement of a material fact or
omit to state a material fact required to be stated therein, or necessary to
make the statements therein not misleading.

         b.   The Company shall prepare and file with the SEC such amendments
(including post-effective amendments) and supplements to the Registration
Statement and the prospectus used in connection with the Registration Statement
as may be necessary to keep the Registration Statement effective at all times
during the Registration Period, and, during such period, comply with the
provisions of the 1933 Act with respect to the disposition of all Registrable
Securities of the Company covered by the Registration Statement until such time
as all of such Registrable Securities have been disposed of in accordance with
the intended methods of disposition by the seller or sellers thereof as set
forth in the Registration Statement.  In the event the number of shares
available under a Registration Statement filed pursuant to this Agreement is
insufficient to cover all of the Registrable Securities issued or issuable upon
conversion of the Debentures, the Company shall amend the Registration
Statement, or file a new Registration Statement (on the short form available
therefore, if applicable), or both, so as to cover all of the Registrable
Securities, in each case, as soon as practicable, but in any event within twenty
(20) business days (subject to reasonable extensions arising from the Company's
obligation to obtain Stockholder Approval (as defined in the Debenture) or to
effect an increase in the authorized number of shares of Common Stock pursuant
to Section 1.7 of the Debenture) after the necessity therefor arises (based on
the market price of the Common Stock and other relevant factors on which the
Company reasonably elects to rely).  The Company shall use its best efforts to
cause such amendment and/or new Registration Statement to become effective as
soon as practicable following the filing thereof.  The provisions of Section
2(c) above shall be applicable with respect to such obligation, with the ninety
(90) days running from the day after the date on which the Company reasonably
first determines (or reasonably should have determined) the need therefor.

         c.   The Company shall furnish to each Investor whose Registrable
Securities are included in the Registration Statement and its legal counsel (i)
promptly after the same is prepared and 

                                 Exhibit 4.2 - Page 5


publicly distributed, filed with the SEC, or received by the Company, one copy
of the Registration Statement and any amendment thereto, each preliminary
prospectus and prospectus and each amendment or supplement thereto, and, in the
case of the Registration Statement referred to in Section 2(a), each letter
written by or on behalf of the Company to the SEC or the staff of the SEC, and
each item of correspondence from the SEC or the staff of the SEC, in each case
relating to such Registration Statement (other than any portion of any thereof
which contains information for which the Company has sought confidential
treatment), and (ii) such number of copies of a prospectus, including a
preliminary prospectus, and all amendments and supplements thereto and such
other documents as such Investor may reasonably request in order to facilitate
the disposition of the Registrable Securities owned by such Investor.  The
Company will immediately notify each Investor by facsimile of the effectiveness
of the Registration Statement or any post-effective amendment.

         d.   The Company shall use reasonable efforts to (i) register and
qualify the Registrable Securities covered by the Registration Statement under
such other securities or "blue sky" laws of such jurisdictions in the United
States as the Investors who hold a majority in interest of the Registrable
Securities being offered reasonably request, (ii) prepare and file in those
jurisdictions such amendments (including post-effective amendments) and
supplements to such registrations and qualifications as may be necessary to
maintain the effectiveness thereof during the Registration Period, (iii) take
such other actions as may be necessary to maintain such registrations and
qualifications in effect at all times during the Registration Period, and (iv)
take all other actions reasonably necessary or advisable to qualify the
Registrable Securities for sale in such jurisdictions; PROVIDED, HOWEVER, that
the Company shall not be required in connection therewith or as a condition
thereto to (a) qualify to do business in any jurisdiction where it would not
otherwise be required to qualify but for this Section 3(d), (b) subject itself
to general taxation in any such jurisdiction, (c) file a general consent to
service of process in any such jurisdiction, or (d) make any change in its
charter or bylaws, which in each case the Board of Directors of the Company
determines to be contrary to the best interests of the Company and its
stockholders.

         e.   In the event Investors who hold a majority-in-interest of the
Registrable Securities being offered in the offering  (with the approval of a
majority-in-interest of the Initial Investors, so long as such Initial Investors
own, in the aggregate, at least 50% of the then outstanding Registerable
Securities) select underwriters for the offering, the Company shall enter into
and perform its obligations under an underwriting agreement, in usual and
customary form, including, without limitation, customary indemnification and
contribution obligations, with the underwriters of such offering.  

         f.   As promptly as practicable after becoming aware of such event,
the Company shall notify each Investor of the happening of any event, of which
the Company has knowledge, as a result of which the prospectus included in the
Registration Statement, as then in effect, includes an untrue statement of a
material fact or omission to state a material fact required to be stated therein
or necessary to make the statements therein not misleading, and use its best
efforts promptly to prepare a supplement or amendment to the Registration
Statement to correct such untrue statement or omission, 

                                 Exhibit 4.2 - Page 6


and deliver such number of copies of such supplement or amendment to each
Investor as such Investor may reasonably request; provided that, for not more
than fifteen (15) consecutive trading days (or a total of not more than (i)
twenty (20) trading days in any four (4) month period or (ii) forty-five (45)
trading days in any twelve (12) month period), the Company may delay the
disclosure of material non-public information concerning the Company the
disclosure of which at the time is not, in the good faith opinion of the Board
of Directors of the Company, in the best interests of the Company and, in the
opinion of counsel to the Company, otherwise required (an "Allowed Delay");
provided, further, that the Company shall promptly (i) notify the Investors in
writing of the existence of material non-public information giving rise to an
Allowed Delay and (ii) advise the Investors in writing to cease all sales under
the Registration Statement until the end of the Allowed Delay.  Upon expiration
of the Allowed Delay, the Company shall again be bound by the first sentence of
this Section 3(f) with respect to the information giving rise thereto.

         g.   The Company shall use its best efforts to prevent the issuance of
any stop order or other suspension of effectiveness of a Registration Statement,
and, if such an order is issued, to obtain the withdrawal of such order at the
earliest possible moment and to notify each Investor who holds Registrable
Securities being sold (or, in the event of an underwritten offering, the
managing underwriters) of the issuance of such order and the resolution thereof.

         h.   The Company shall permit a single firm of counsel designated by
the Initial Investors to review the Registration Statement and all amendments
and supplements thereto (as well as all requests for acceleration or
effectiveness thereof) a reasonable period of time prior to their filing with
the SEC, and not file any document in a form to which such counsel reasonably
objects and will not request acceleration of the Registration Statement without
prior notice to such counsel.

         i.   The Company shall make generally available to its security
holders as soon as practical, but not later than ninety (90) days after the
close of the period covered thereby, an earnings statement (in form complying
with the provisions of Rule 158 under the 1933 Act) covering a twelve-month
period beginning not later than the first day of the Company's fiscal quarter
next following the effective date of the Registration Statement.

         j.   At the request of any Investor, the Company shall furnish, on the
date that Registrable Securities are delivered to an underwriter, if any, for
sale in connection with the Registration Statement, (i) an opinion, dated as of
such date, from counsel representing the Company for purposes of such
Registration Statement, in form, scope and substance as is customarily given in
an underwritten public offering, addressed to the underwriters and the Investors
and (ii) a letter, dated such date, from the Company's independent certified
public accountants in form and substance as is customarily given by independent
certified public accountants to underwriters in an underwritten public offering,
addressed to the underwriters and the Investors.

         k.   The Company shall make available for inspection by (i) any
Investor, (ii) any underwriter participating in any disposition pursuant to the
Registration Statement, (iii) one firm of 

                                 Exhibit 4.2 - Page 7


attorneys and one firm of accountants or other agents retained by the Initial
Investors, (iv) one firm of attorneys and one firm of accountants or other
agents retained by all other Investors, and (v) one firm of attorneys retained
by all such underwriters (collectively, the "INSPECTORS") all pertinent
financial and other records, and pertinent corporate documents and properties of
the Company (collectively, the "RECORDS"), as shall be reasonably deemed
necessary by each Inspector to enable each Inspector to exercise its due
diligence responsibility, and cause the Company's officers, directors and
employees to supply all information which any Inspector may reasonably request
for purposes of such due diligence; PROVIDED, HOWEVER, that each Inspector and
Investor shall hold in confidence and shall not make any disclosure (except, in
the case of an Inspector, to an Investor) of any Record or other information
which the Company determines in good faith to be confidential, and of which
determination the Inspectors are so notified, unless (a) the disclosure of such
Records is necessary to avoid or correct a misstatement or omission in any
Registration Statement, (b) the release of such Records is ordered pursuant to a
subpoena or other order from a court or government body of competent
jurisdiction, or (c) the information in such Records has been made generally
available to the public other than by disclosure in violation of this or any
other agreement.  The Company shall not be required to disclose any confidential
information in such Records to any Inspector until and unless such Inspector
shall have entered into confidentiality agreements (in form and substance
satisfactory to the Company) with the Company with respect thereto,
substantially in the form of this Section 3(k).  Each Investor agrees that it
shall, upon learning that disclosure of such Records is sought in or by a court
or governmental body of competent jurisdiction or through other means, give
prompt notice to the Company and allow the Company, at its expense, to undertake
appropriate action to prevent disclosure of, or to obtain a protective order
for, the Records deemed confidential.  Nothing herein shall be deemed to limit
the Investors' ability to sell Registrable Securities in a manner which is
otherwise consistent with applicable laws and regulations. 

         l.   The Company shall hold in confidence and not make any disclosure
of information concerning an Investor provided to the Company unless (i)
disclosure of such information is necessary to comply with federal or state
securities laws, (ii) the disclosure of such information is necessary to avoid
or correct a misstatement or omission in any Registration Statement, (iii) the
release of such information is ordered pursuant to a subpoena or other order
from a court or governmental body of competent jurisdiction, or (iv) such
information has been made generally available to the public other than by
disclosure in violation of this or any other agreement.  The Company agrees that
it shall, upon learning that disclosure of such information concerning an
Investor is sought in or by a court or governmental body of competent
jurisdiction or through other means, give prompt notice to such Investor prior
to making such disclosure, and allow the Investor, at its expense, to undertake
appropriate action to prevent disclosure of, or to obtain a protective order
for, such information.

         m.   The Company shall use its best efforts either to (i) cause all
the Registrable Securities covered by the Registration Statement to be listed on
each national securities exchange on which securities of the same class or
series issued by the Company are then listed, if any, if the listing of such
Registrable Securities is then permitted under the rules of such exchange, or
(ii) secure the designation and quotation, of all the Registrable Securities
covered by the Registration Statement on 

                                 Exhibit 4.2 - Page 8


the Nasdaq-NMS or, if not eligible for the Nasdaq-NMS on the Nasdaq SmallCap
and, without limiting the generality of the foregoing, to arrange for at least
two market makers to register with the National Association of Securities
Dealers, Inc. ("NASD") as such with respect to such Registrable Securities.

         n.   The Company shall provide a transfer agent and registrar, which
may be a single entity, for the Registrable Securities not later than the
effective date of the Registration Statement.

         o.   The Company shall cooperate with the Investors who hold
Registrable Securities being offered and the managing underwriter or
underwriters, if any, to facilitate the timely preparation and delivery of
certificates (not bearing any restrictive legends) representing Registrable
Securities to be offered pursuant to the Registration Statement and enable such
certificates to be in such denominations or amounts, as the case may be, as the
managing underwriter or underwriters, if any, or the Investors may reasonably
request and registered in such names as the managing underwriter or
underwriters, if any, or the Investors may request, and, within three (3)
business days after a Registration Statement which includes Registrable
Securities is ordered effective by the SEC, the Company shall deliver, and shall
cause legal counsel selected by the Company to deliver, to the transfer agent
for the Registrable Securities (with copies to the Investors whose Registrable
Securities are included in such Registration Statement) an instruction in the
form attached hereto as EXHIBIT 1 and an opinion of such counsel in the form
attached hereto as EXHIBIT 2.

         p.   The Company shall cooperate with the Investors to effectuate the
intent of this Agreement.

    4.   OBLIGATIONS OF THE INVESTORS.

    In connection with the registration of the Registrable Securities, the
Investors shall have the following obligations:

         a.   It shall be a condition precedent to the obligations of the
Company to complete the registration pursuant to this Agreement with respect to
the Registrable Securities of a particular Investor that such Investor shall
furnish to the Company such information regarding itself, the Registrable
Securities held by it and the intended method of disposition of the Registrable
Securities held by it as shall be reasonably required to effect the registration
of such Registrable Securities and shall execute such documents in connection
with such registration as the Company may reasonably request.  At least five (5)
business days prior to the first anticipated filing date of the Registration
Statement, the Company shall notify each Investor of the information the Company
requires from each such Investor. 

         b.   Each Investor, by such Investor's acceptance of the Registrable
Securities, agrees to cooperate with the Company as reasonably requested by the
Company in connection with the 

                                 Exhibit 4.2 - Page 9


preparation and filing of the Registration Statement hereunder, unless such
Investor has notified the Company in writing of such Investor's election to
exclude all of such Investor's Registrable Securities from the Registration
Statement.

         c.   In the event Investors holding a majority-in-interest of the
Registrable Securities being registered (with the approval of the Initial
Investors, so long as such Initial Investors own, in the aggregate, at least 50%
of the then outstanding Registerable Securities) determine to engage the
services of an underwriter, each Investor agrees to enter into and perform such
Investor's obligations under an underwriting agreement, in usual and customary
form, including, without limitation, customary indemnification and contribution
obligations, with the managing underwriter of such offering and take such other
actions as are reasonably required in order to expedite or facilitate the
disposition of the Registrable Securities, unless such Investor has notified the
Company in writing of such Investor's election to exclude all of such Investor's
Registrable Securities from the Registration Statement.

         d.   Each Investor agrees that, upon receipt of any notice from the
Company of the happening of any event of the kind described in Section 3(f) or
3(g), such Investor will immediately discontinue disposition of Registrable
Securities pursuant to the Registration Statement covering such Registrable
Securities until such Investor's receipt of the copies of the supplemented or
amended prospectus contemplated by Section 3(f) or 3(g) and, if so directed by
the Company, such Investor shall deliver to the Company (at the expense of the
Company) or destroy (and deliver to the Company a certificate of destruction)
all copies in such Investor's possession, of the prospectus covering such
Registrable Securities current at the time of receipt of such notice.

         e.   No Investor may participate in any underwritten registration
hereunder unless such Investor (i) agrees to sell such Investor's Registrable
Securities on the basis provided in any underwriting arrangements in usual and
customary form entered into by the Company, (ii) completes and executes all
questionnaires, powers of attorney, indemnities, underwriting agreements and
other documents reasonably required under the terms of such underwriting
arrangements, and (iii) agrees to pay its pro rata share of all underwriting
discounts and commissions and any expenses in excess of those payable by the
Company pursuant to Section 5 below.

    5.   EXPENSES OF REGISTRATION.

    All reasonable expenses, other than underwriting discounts and commissions,
incurred in connection with registrations, filings or qualifications pursuant to
Sections 2 and 3, including, without limitation, all registration, listing and
qualification fees, printers and accounting fees, the fees and disbursements of
counsel for the Company, and the reasonable fees and disbursements of counsel
selected by the Initial Investors pursuant to Sections 2(b) and 3(h) hereof
shall be borne by the Company.

                                Exhibit 4.2 - Page 10


    6.   INDEMNIFICATION.

    In the event any Registrable Securities are included in a Registration
Statement under this Agreement:

         a.   To the extent permitted by law, the Company will indemnify, hold
harmless and defend (i) each Investor who holds such Registrable Securities,
(ii) the directors, officers, partners, employees, agents and each person who
controls any Investor within the meaning of the 1933 Act or the Securities
Exchange Act of 1934, as amended (the "1934 ACT"), if any, (iii) any underwriter
(as defined in the 1933 Act) for the Investors, and (iv) the directors,
officers, partners, employees and each person who controls any such underwriter
within the meaning of the 1933 Act or the 1934 Act, if any (each, an
"INDEMNIFIED PERSON"), against any joint or several losses, claims, damages,
liabilities or expenses (collectively, together with actions, proceedings or
inquiries by any regulatory or self-regulatory organization, whether commenced
or threatened, in respect thereof, "CLAIMS") to which any of them may become
subject insofar as such Claims arise out of or are based upon: (i) any untrue
statement or alleged untrue statement of a material fact in a Registration
Statement or the omission or alleged omission to state therein a material fact
required to be stated or necessary to make the statements therein not
misleading; (ii) any untrue statement or alleged untrue statement of a material
fact contained in any preliminary prospectus if used prior to the effective date
of such Registration Statement, or contained in the final prospectus (as amended
or supplemented, if the Company files any amendment thereof or supplement
thereto with the SEC) or the omission or alleged omission to state therein any
material fact necessary to make the statements made therein, in light of the
circumstances under which the statements therein were made, not misleading; or
(iii) any violation or alleged violation by the Company of the 1933 Act, the
1934 Act, any other law, including, without limitation, any state securities
law, or any rule or regulation thereunder relating to the offer or sale of the
Registrable Securities (the matters in the foregoing clauses (i) through (iii)
being, collectively, "VIOLATIONS").  Subject to the restrictions set forth in
Section 6(c) with respect to the number of legal counsel, the Company shall
reimburse the Indemnified Person, promptly as such expenses are incurred and are
due and payable, for any reasonable legal fees or other reasonable expenses
incurred by them in connection with investigating or defending any such Claim. 
Notwithstanding anything to the contrary contained herein, the indemnification
agreement contained in this Section 6(a): (i) shall not apply to a Claim arising
out of or based upon a Violation which occurs in reliance upon and in conformity
with information furnished in writing to the Company by any Indemnified Person
or underwriter for such Indemnified Person expressly for use in connection with
the preparation of the Registration Statement or any such amendment thereof or
supplement thereto, if such prospectus was timely made available by the Company
pursuant to Section 3(c) hereof; (ii) shall not apply to amounts paid in
settlement of any Claim if such settlement is effected without the prior written
consent of the Company, which consent shall not be unreasonably withheld; and
(iii) with respect to any preliminary prospectus, shall not inure to the benefit
of any Indemnified Person if the untrue statement or omission of material fact
contained in the preliminary prospectus was corrected on a timely basis in the
prospectus, as then amended or supplemented, such corrected prospectus was
timely made available by the Company pursuant to Section 3(c) hereof, and the
Indemnified Person was promptly advised in writing not to use the 

                                Exhibit 4.2 - Page 11


incorrect prospectus prior to the use giving rise to a Violation and such
Indemnified Person, notwithstanding such advice, used it.  Such indemnity shall
remain in full force and effect regardless of any investigation made by or on
behalf of the Indemnified Person and shall survive the transfer of the
Registrable Securities by the Investors pursuant to Section 9.

         b.   In connection with any Registration Statement in which an
Investor is participating, each such Investor agrees severally and not jointly
to indemnify, hold harmless and defend, to the same extent and in the same
manner set forth in Section 6(a), the Company, each of its directors, each of
its officers who signs the Registration Statement, each person, if any, who
controls the Company within the meaning of the 1933 Act or the 1934 Act, any
underwriter and any other stockholder selling securities pursuant to the
Registration Statement or any of its directors or officers or any person who
controls such stockholder or underwriter within the meaning of the 1933 Act or
the 1934 Act (collectively and together with an Indemnified Person, an
"INDEMNIFIED PARTY"), against any Claim to which any of them may become subject,
under the 1933 Act, the 1934 Act or otherwise, insofar as such Claim arises out
of or is based upon any Violation by such Investor, in each case to the extent
(and only to the extent) that such Violation occurs in reliance upon and in
conformity with written information furnished to the Company by such Investor
expressly for use in connection with such Registration Statement or such
Violation is a failure of such Investor to comply with applicable prospectus
delivery requirements under the 1933 Act (and such failure was not caused, in
whole or in part, by any action or failure to act by the Company or any third
party, so long as such Investor used reasonable efforts to comply with such
requirements); and subject to Section 6(c) such Investor will reimburse any
legal or other expenses (promptly as such expenses are incurred and are due and
payable) reasonably incurred by them in connection with investigating or
defending any such Claim; PROVIDED, HOWEVER, that the indemnity agreement
contained in this Section 6(b) shall not apply to amounts paid in settlement of
any Claim if such settlement is effected without the prior written consent of
such Investor, which consent shall not be unreasonably withheld; PROVIDED,
FURTHER, HOWEVER, that the Investor shall be liable under this Agreement
(including this Section 6(b) and Section 7) for only that amount as does not
exceed the net proceeds to such Investor as a result of the sale of Registrable
Securities pursuant to such Registration Statement.  Such indemnity shall remain
in full force and effect regardless of any investigation made by or on behalf of
such Indemnified Party and shall survive the transfer of the Registrable
Securities by the Investors pursuant to Section 9. Notwithstanding anything to
the contrary contained herein, the indemnification agreement contained in this
Section 6(b) with respect to any preliminary prospectus shall not inure to the
benefit of any Indemnified Party if the untrue statement or omission of material
fact contained in the preliminary prospectus was corrected on a timely basis in
the prospectus, as then amended or supplemented.

         c.   Promptly after receipt by an Indemnified Person or Indemnified
Party under this Section 6 of notice of the commencement of any action
(including any governmental action), such Indemnified Person or Indemnified
Party shall, if a Claim in respect thereof is to be made against any
indemnifying party under this Section 6, deliver to the indemnifying party a
written notice of the commencement thereof, and the indemnifying party shall
have the right to participate in, and, to the extent the indemnifying party so
desires, jointly with any other indemnifying party similarly noticed, to 

                                Exhibit 4.2 - Page 12


assume control of the defense thereof with counsel mutually satisfactory to the
indemnifying party and the Indemnified Person or the Indemnified Party, as the
case may be; PROVIDED, HOWEVER, that an Indemnified Person or Indemnified Party
shall have the right to retain its own counsel with the fees and expenses to be
paid by the indemnifying party, if, in the reasonable opinion of counsel
retained by the indemnifying party, the representation by such counsel of the
Indemnified Person or Indemnified Party and the indemnifying party would be
inappropriate due to actual or potential differing interests between such
Indemnified Person or Indemnified Party and any other party represented by such
counsel in such proceeding.  The indemnifying party shall pay for only one
separate legal counsel for  the Indemnified Persons or the Indemnified Parties,
as applicable, and such legal counsel shall be selected by Investors holding a
majority-in-interest of the  Registrable Securities included in the Registration
Statement to which the Claim relates (with the approval of a majority-in-
interest of the Initial Investors, so long as such Initial Investors own, in the
aggregate, at least 50% of the then outstanding Registerable Securities), if the
Investors are entitled to indemnification hereunder, or the Company, if the
Company is entitled to indemnification hereunder, as applicable.  The failure to
deliver written notice to the indemnifying party within a reasonable time of the
commencement of any such action shall not relieve such indemnifying party of any
liability to the Indemnified Person or Indemnified Party under this Section 6,
except to the extent that the indemnifying party is actually prejudiced in its
ability to defend such action.  The indemnification required by this Section 6
shall be made by periodic payments of the amount thereof during the course of
the investigation or defense, as such expense, loss, damage or liability is
incurred and is due and payable.

    7.   CONTRIBUTION.  

    To the extent any indemnification by an indemnifying party is prohibited or
limited by law, the indemnifying party agrees to make the maximum contribution
with respect to any amounts for which it would otherwise be liable under Section
6 to the fullest extent permitted by law; PROVIDED, HOWEVER, that (i) no
contribution shall be made under circumstances where the maker would not have
been liable for indemnification under the fault standards set forth in Section
6, (ii) no seller of Registrable Securities guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the 1933 Act) shall be
entitled to contribution from any seller of Registrable Securities who was not
guilty of such fraudulent misrepresentation, and (iii) contribution (together
with any indemnification or other obligations under this Agreement) by any
seller of Registrable Securities shall be limited in amount to the net amount of
proceeds received by such seller from the sale of such Registrable Securities.

    8.   REPORTS UNDER THE 1934 ACT.  

    With a view to making available to the Investors the benefits of Rule 144
promulgated under the 1933 Act or any other similar rule or regulation of the
SEC that may at any time permit the investors to sell securities of the Company
to the public without registration ("RULE 144"), the Company agrees to:

         a.   make and keep public information available, as those terms are
understood and 

                                Exhibit 4.2 - Page 13


defined in Rule 144;

         b.   file with the SEC in a timely manner all reports and other
documents required of the Company under the 1933 Act and the 1934 Act so long as
the Company remains subject to such requirements (it being understood that
nothing herein shall limit the Company's obligations under Section 4(c) of the
Securities Purchase Agreement) and the filing of such reports and other
documents is required for the applicable provisions of Rule 144; and

         c.   furnish to each Investor so long as such Investor owns
Registrable Securities, promptly upon request, (i) a written statement by the
Company that it has complied with the reporting requirements of Rule 144, the
1933 Act and the 1934 Act, (ii) a copy of the most recent annual or quarterly
report of the Company and such other reports and documents so filed by the
Company, and (iii) such other information as may be reasonably requested to
permit the Investors to sell such securities pursuant to Rule 144 without
registration.

    9.   ASSIGNMENT OF REGISTRATION RIGHTS.  

    The rights under this Agreement shall be automatically assignable by the
Investors to any transferee of all or any portion of Registrable Securities if:
(i) the Investor agrees in writing with the transferee or assignee to assign
such rights, and a copy of such agreement is furnished to the Company within a
reasonable time after such assignment, (ii) the Company is, within a reasonable
time after such transfer or assignment, furnished with written notice of (a) the
name and address of such transferee or assignee, and (b) the securities with
respect to which such registration rights are being transferred or assigned,
(iii) following such transfer or assignment, the further disposition of such
securities by the transferee or assignee is restricted under the 1933 Act and
applicable state securities laws, (iv) at or before the time the Company
receives the written notice contemplated by clause (ii) of this sentence, the
transferee or assignee agrees in writing with the Company to be bound by all of
the provisions contained herein, (v) such transfer shall have been made in
accordance with the applicable requirements of the Securities Purchase
Agreement, and (vi) such transferee shall be an "ACCREDITED INVESTOR" as that
term defined in Rule 501 of Regulation D promulgated under the 1933 Act.

    10.  AMENDMENT OF REGISTRATION RIGHTS.  

    Provisions of this Agreement may be amended and the observance thereof may
be waived (either generally or in a particular instance and either retroactively
or prospectively), only with written consent of the Company, each of the Initial
Investors (to the extent such Initial Investor still owns Registrable
Securities) and Investors who hold a majority interest of the Registrable
Securities.  Any amendment or waiver effected in accordance with this Section 10
shall be binding upon each Investor and the Company.




                                Exhibit 4.2 - Page 14


    11.  MISCELLANEOUS.

         a.   A person or entity is deemed to be a holder of Registrable
Securities whenever such person or entity owns of record such Registrable
Securities.  If the Company receives conflicting instructions, notices or
elections from two or more persons or entities with respect to the same
Registrable Securities, the Company shall act upon the basis of instructions,
notice or election received from the registered owner of such Registrable
Securities.

         b.   Any notices required or permitted to be given under the terms
hereof shall be sent by certified or registered mail (return receipt requested)
or delivered personally or by courier (including a recognized overnight delivery
service) or by facsimile and shall be effective five days after being placed in
the mail, if mailed by regular U.S. mail, or upon receipt, if delivered
personally or by courier (including a recognized overnight delivery service) or
by facsimile, in each case addressed to a party.  The addresses for such
communications shall be:

    If to the Company:

    Zitel Corporation
    47211 Bayside Parkway
    Fremont, California 94538
    Attention: Chief Financial Officer
    Facsimile: (510) 440-8526
    
    With copy to:

    Cooley Godward Castro Haddleson & Tatum
    One Maritime Plaza, 20th Floor     
    San Francisco, California  94111-3580
    Attention:  John Cardoza, Esquire
    Facsimile:  (415) 951-3699
    

If to an Investor: to the address set forth immediately below such Investor's
name on the signature pages to the Securities Purchase Agreement. 

         c.   Failure of any party to exercise any right or remedy under this
Agreement or otherwise, or delay by a party in exercising such right or remedy,
shall not operate as a waiver thereof.

         d.   This Agreement shall be enforced, governed by and construed in
accordance with the laws of the California applicable to agreements made and to
be performed entirely within such State.  In the event that any provision of
this Agreement is invalid or unenforceable under any applicable statute or rule
of law, then such provision shall be deemed inoperative to the extent that it 

                                Exhibit 4.2 - Page 15


may conflict therewith and shall be deemed modified to conform with such statute
or rule of law.  Any provision hereof which may prove invalid or unenforceable
under any law shall not affect the validity or enforceability of any other
provision hereof.  

         e.   This Agreement and the Securities Purchase Agreement (including
all schedules and exhibits thereto) constitute the entire agreement among the
parties hereto with respect to the subject matter hereof and thereof.  There are
no restrictions, promises, warranties or undertakings, other than those set
forth or referred to herein and therein.  This Agreement and the Securities
Purchase Agreement supersede all prior agreements and understandings among the
parties hereto with respect to the subject matter hereof and thereof.

         f.   Subject to the requirements of Section 9 hereof, this Agreement
shall inure to the benefit of and be binding upon the successors and assigns of
each of the parties hereto.

         g.   The headings in this Agreement are for convenience of reference
only and shall not limit or otherwise affect the meaning hereof.

         h.   This Agreement may be executed in two or more counterparts, each
of which shall be deemed an original but all of which shall constitute one and
the same agreement.  This Agreement, once executed by a party, may be delivered
to the other party hereto by facsimile transmission of a copy of this Agreement
bearing the signature of the party so delivering this Agreement.

         i.   Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

         j.   All consents and other determinations to be made by the Investors
pursuant to this Agreement shall be made by Investors holding a majority of the
Registrable Securities, determined as if the Debentures then outstanding have
been converted into or exercised for Registrable Securities.

         k.   The language used in this Agreement will be deemed to be the
language chosen by the parties to express their mutual intent, and no rules of
strict construction will be applied against any party.



                  [REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]



                                Exhibit 4.2 - Page 16


    IN WITNESS WHEREOF, the Company and the undersigned Initial Investor have
caused this Agreement to be duly executed as of the date first above written

ZITEL CORPORATION

By:      Henry C. Harris
Name:    Henry C. Harris
Its:     Chief Financial Officer


RGC INTERNATIONAL INVESTORS, LDC

By: Rose Glen Capital Management, L.P., Investment Manager
    By: RGC General Partner Corp.

By:      Wayne D. Bloch
Name:    Wayne D. Bloch
Its:     Managing Director


HALIFAX FUND L.P.

By:  Palladin Group L.P., as attorney in fact
    By:  Palladin Capital Management, LLC, General Partner

By:      Andrew Kaplan
Name:    Andrew Kaplan
Its:     Senior Vice President


NELSON PARTNERS

By:      Anne Dupuy
Name:    Anne Dupuy
Its:     Officer


OLYMPUS SECURITIES, LTD.

By:      Anne Dupuy
Name:    Anne Dupuy
Its:     Alternate Director

                                Exhibit 4.2 - Page 17