The main instance's value for TD_INSTANCE_NUM is one and the workers’ instance values for TD_INSTANCE_NUM starts at two and increments with each new worker. An instance’s number is used to access its designated area within the TELINFO area. No two instances can have the same value for TD_INSTANCE_NUM. The value for TD_INSTANCE_NUM cannot be greater than the value for TD_MAX_INSTANCES.
In a multiple-instance environment, only the main instance uses the TD_MAX_SESSIONS and TD_MIN_SESSIONS attributes. The main instance will distribute the sessions amongst itself and the worker instances. The number of sessions needs to be greater than or equal to the number of instances. If no session preferences are specified, the default will be one session per instance.
Beyond these attributes, all other attributes, schemas, and DML groups must be the same for both the main and the worker instances.