Setting up a multi-server configuration

When you set up a multi-server configuration (that is, a configuration that has more than one broker server), some settings differ from those specified for a single-server configuration:

  • Specify the group attachment name instead of a DB2® subsystem ID (SSID) for:
    • The db2.jcc.ssid keyword of the DB2JccConfiguration.properties file
    • The MVSDEFAULTSSID initialization parameter in the ODBC initialization file DSNAOINI (the connecting data sharing member is then selected based on the subsystem name list and the subsystem status)
    To obtain the group attachment name of the data sharing group, issue the DISPLAY GROUP command.
  • Use a common WLM application environment. A WLM application environment must be available when you install the stored procedures. In the definition of the application environment, specify the generic symbol &IWMSSNM as the value of the start parameter DB2SSN. This lets you use the same application environment JCL procedure for all members of the data sharing group. The procedures described in Preparing the runtime system on which the database is located assume that this procedure and the Java™ environment data set that is allocated by the procedure is on a shared volume.
  • If you use a common shared HFS for all your broker servers, this means that you install the stored procedures once for the initial broker server in such a way that they are automatically made available to all broker servers that you subsequently create for the instance. However, if you have a separate HFS file system for each of your broker servers, note that the procedures use DB2 packages that are grouped into a single collection. The name of this collection is identical to the schema name, which is specified by the customization placeholder DNIvSN. The DB2 packages in this collection must match the Java class files and the serialized profile that is generated when you set up the initial broker server. Therefore, for each additional broker server, you must copy the class files and the serialized profiles from the deployment directory of your initial broker server to a corresponding class path with exactly the same name in the new broker server environment. This is important, because the name of the class path is specified in the Java environment data set, and this data set is shared by all broker servers.
  • Provide DB2 group buffer pools for the table spaces and indexes.