In planning for database generation, you can choose two names for your database. The first name is the server name that the users will specify. The second name is the resid (VM resource identifier) that identifies the application server to VM. The server name and the resid can be the same if the requirements for both are met. If the server name is longer than 8 characters, then you must choose a resid. You must also decide whether the application server can be accessed from other processors.
| Note: | When using remote access, it is recommended that the system administrator ensure that server names are unique within a set of interconnected SNA networks, and that resids are unique in a TSAF collection or a gateway. (A gateway is also referred to as an LU.) The resid must also be identified with a GLOBAL scope. For more information about these requirements, see Distributed Processing Administration. |
The server name must be from 1 to 18 characters. It should start with an alphabetic character which can be followed by alphabetic characters, numeric characters, or underscores. The server name should be unique within a set of networks that are interconnected. The server name is stored in the resid SQLDBN file on the production minidisk.
The resid must start with an alphanumeric character and be from 1 to 8 characters. The terms resid and the TPN (transaction program name) are synonymous. The resid is used to identify the database resource to the VM system, and in combination with the NETID and LU name (AVS gateway name) provides the network address of the resource. The resid can also be a 4 byte hex TPN such as the DRDA default TPN x'07F6C4C2'. However, there is little need to define a hexadecimal resid for an application server. The use of a character resid is preferred because it is more readable.
To specify a value for resid that is different from that specified for the server name, you must create an entry in the RESID NAMES file that is on the accessed production minidisk of the application server. This file correlates the server name and the resid. The resid defaults to the server name if:
For ease of administration, it is best to keep the resid identical to the server name. If the two names are not identical, the VM users accessing the application server must also access a CMS communication Directory that has an entry defined for this server and resid (known as the :dbname and :tpn tags respectively) even if both the user and the application server are in the same TSAF collection.