Chapter 5. Other Common Service Layer (CSL) functionalities 119
used, DBRC will behave as if the sample version of the exit was being used. DSPSCIX0 has
the ability to set, modify, accept or reject IMSPLEX name for DBRC registration to SCI.
DSPSCIX0 must be found in an authorized library or in LINKLST. If DSPSCIX0 is found in a
concatenated STEPLIB or JOBLIB, only the data set containing DSPSCIX0 must be
authorized. If DSPSCIX0 is found in LINKLST, no authorization check is performed.
We recommend that you use your own customized user exit rather than the execution
parameter if you feel comfortable coding this exit routine. The exit routine must be named
DSPSCIX0 and may be used to decide if a DBRC instance should register with SCI and
which IMSplex name it should use.
The data set name of one of the RECON data sets (RECON1, RECON2 or RECON3) is
passed to the exit routine. If an “IMSPLEX=” execution parameter is provided, this value (one
to five characters) is passed to the exit routine as well.
The exit passes back a return code to indicate the intended registration action to take and the
IMSplex name to use, if the decision was made to register this DBRC instance.
DSPSCIX0 return codes
The return codes are listed in Table 5-7.
Table 5-7 Return codes of the DSPSCIX0 exit
5.12 Implementing ARLN
The use of automatic RECON loss notification feature is optional and is automatically enabled
The SCI address space is up and running on the same LPAR.
The DBRC instance registers with SCI as a member SCI’s IMSplex.
ARLN requires that an IMSplex name be specified and that SCI is active. The IMSplex name
may be specified by the DBRC SCI exit routine. Since the exit routine could be used with
DBRC instances using different RECONs, the exit routine should be able to handle different
Return code Meaning and comment
‘0000 IMSplex name is used to register with SCI (ARLN invoked)
No SCI registration; RECON access fails if the RECON contains an
IMSplex name. Use this to avoid (accidental) registrations or if you do not
want to use ARLN. This would also prevent any job step with any IMSplex
name specified from setting the IMSplex name in the RECONs, if it is not
yet set.
‘0008 No SCI registration; any IMSplex name found in RECON is ignored and the
RECON access is allowed.
Use this with caution! Maybe you should provide
a special copy of your exit routine for using this option only in emergency
cases. Access to this exit routine should be restricted to authorized
personnel only!
‘0012 RECON access denied; SCI registration fails or could not be attempted
for severe reasons, for example, because of an exit error. This generally
results in an IMS user abend 2480.

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