Multiple instances (Windows)

It is possible to run multiple instances of the Db2® database manager on the same computer. Each instance of the database manager maintains its own databases and has its own database manager configuration parameters.

Note: The instances can also belong to different Db2 copies on a computer that can be at different levels of the database manager. If you are running a 64-bit Windows system, you can install 32-bit Db2, or 64-bit Db2 but they cannot co-exist on the same machine.

An instance of the database manager consists of the following:

  • A Windows service that represents the instance. The name of the service is same as the instance name. The display name of the service (from the Services panel) is the instance name, prefixed with the Db2 - string. For example, for an instance named Db2, there exists a Windows service called Db2 with a display name of Db2 - Db2 Copy Name - Db2.
    Note: A Windows service is not created for client instances.
  • An instance directory. This directory contains the database manager configuration files, the system database directory, the node directory, the Database Connection Services (DCS) directory, all the diagnostic log and dump files that are associated with the instance. The instance directory varies from edition to edition of the Windows family of operating systems; to verify the default directory on Windows, check the setting of the DB2INSTPROF environment variable using the command db2set DB2INSTPROF. You can also change the default instance directory by changing the DB2INSTPROF environment variable. For example, to set it to c:\DB2PROFS:
    • Set DB2INSTPROF to c:\DB2PROFS using the db2set.exe -g command
    • Run DB2ICRT.exe command to create the instance.
  • When you create an instance on Windows operating systems, the default locations for user data files, such as instance directories and the db2cli.ini file, is Program Data\IBM\DB2\Copy Name where Copy Name represents the Db2 copy name.
    Note: The location of the db2cli.ini file might change based on whether the Microsoft ODBC Driver Manager is used, the type of data source names (DSN) used, the type of client or driver being installed, and whether the registry variable DB2CLIINIPATH is set.