[Exim] CDB lookup / redirect rule

I am currently delivering/redirecting incoming email via a mailhub to various remote mailhost servers by means of LDAP lookup on the mailhub, and I want to change to use CDB lookup
on the mailhub instead.
I produce a txt file in the following format with the local part of the email alias on the left of the colon (k.jackson), and the final delivery point on the right side of the
colon (jacksonk@???), which I compile into a CDB file.

k.jackson:jacksonk@???
j.smith:smithj@???
f.brown:brownf@???

I recieve the email on the mailhub addressed to K.Jackson@??? and want to take the local part (K.Jackson) and lookup in the CDB file and deliver the email to
jacksonk@??? ( a different mailhost server).


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with Exim v3, we have a director:

cdb_lookup:
driver = aliasfile
file = /exim/staff.cdb
search_type = cdb
# user = exim
file_transport = address_file
pipe_transport = address_pipe

--------------------------------------
with Exim v4, is it a router??

cdb_lookup:
driver = redirect
allow_fail
allow_defer
data = cdb;/exim/staff.cdb
# user = exim
file_transport = address_file
pipe_transport = address_pipe

-----------------------------------

How exactly does it look up the local part of the incoming alias (K.Jackson) on the left-hand side of the colon in the CDB file, and redirect/deliver it to the full address on the
left-hand side of the colon?


--

Regards,

- - - - - - - - - - - - - - - -

Ken Jackson.
Unix & Email Systems Administrator,
ICT Systems and Services (North Campus).
London Metropolitan University,
166-220 Holloway Road,
London, N7 8DB.

Email: K.Jackson@???

Tel: +44 (0)207-753-3163 (Ext: 2504)
Fax: +44 (0)207-753-

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