Installing a second Db2 subsystem

When you install a second Db2 subsystem, some installation jobs are optional, some jobs are required, and some jobs are required under certain circumstances.

To install a second subsystem:

1. Optional: Run job DSNTIJSS
   You can use job DSNTIJSS to create an SMS environment for the Db2 catalog and directory data sets. Data sets for the Db2 catalog and directory are managed by Db2 and must be SMS-managed. The SMS environment that you use for Db2 catalog and directory data sets must be established before you begin installation or migration to Db2 12. The SMS environment must include a data class for allocating the data sets in extended format and using extended addressability.
2. Run job DSNTIJCA if you are defining a new ICF catalog.
3. Run job DSNTIJMV.
   Add another subsystem name and subsystem recognition character to IEFSSNxx. LNKLSTxx modifications are needed only for separate libraries.

   For separate libraries, add STEPLIB statements to the precompile and bind steps for program preparation. Add STEPLIB statements for the Db2 offline utilities. Choose a naming convention for any new procedures, and change those as needed.

   For a single library, you must add the exit module data set (prefix.SDSNEXIT) to the STEPLIB statement to contain your changed subsystem parameter. Put this data set first in the STEPLIB concatenation.

4. Run job DSNTIJIN.
   It allocates the following data sets, which contain the sample DBRMs and programs:

   • prefix.DBRMLIB.DATA
   • prefix.SRCLIB.DATA
   • prefix.RUNLIB.LOAD

   Two subsystems cannot share these data sets. If undetected sharing occurs, data could be lost. If you use the same library prefix for both subsystems, change the name of the data sets, unless you do not need them on the first subsystem. Subsequent jobs overwrite them, and then the packages that are bound in the first subsystem do not work with the new load modules.
5. Run job DSNTIJUZ without changes if you use separate libraries. For a single library, provide a separate prefix.SDSNEXIT data set for each subsystem.

   The default SSID displayed by certain panels and procedures is the same for every subsystem. Ensure that the correct subsystem is specified in these cases.

6. Run jobs DSNTIJID, DSNTIJIE, and DSNTIJIF to initialize the Db2 data sets.