CICS® can access
DL/I databases with the CICS-DBCTL interface or by using remote DL/I.
Using DBCTL
This is when DBCTL satisfies the DL/I request issued from the CICS system with the CICS-DBCTL
interface.
Installing and using DBCTL are introduced in this information
(but you also must refer to other CICS and IMS information).
Using remote DL/I
Remote DL/I is done with CICS function
shipping a DL/I request to another CICS system,
in which the DL/I support can be remote DL/I or DBCTL. For more information
about function shipping, see CICS function shipping.
For information about adding remote DL/I support, see Defining DL/I support.
Note:
Although these methods to access DL/I databases can coexist, a
program specification block (PSB) can only contain databases that
are controlled by one of the methods.
CICS Transaction Server
does not support local DL/I.
CICS can also access DL/I
databases in an IMS Database
Manager/Transaction Manager (IMS DM/TM)
system using the CICS-DBCTL interface. This means that you can have
access to DL/I databases controlled by IMS DM/TM
without needing to use IMS data
sharing, if CICS and IMS DM/TM are in the same MVS™ image.
Figure 1 illustrates the three kinds
of DL/I request. Figure 1. DL/I request handling within CICS
Note:
Request #1 is a DBCTL request from CICS A
to DBCTL A for a database controlled by DBCTL A. See CICS-DL/I router (DFHDLI) for a description
of request processing.
Requests #2a and #2b are two separate remote (function shipped)
DL/I requests to databases controlled by, or connected to, other CICS systems (which can be in the
same MVS image or a different
one). There are two ways of issuing such requests:
Request #2a from CICS A
to CICS B for a database controlled
by CICS B.
Request #2b from CICS A
to CICS B for a database controlled
by DBCTL B. The most likely reason for using request #2b is if CICS A and CICS B are in different MVS images.
