Restrictions on names

Specify unique names for all VTAM-related definitions that are active concurrently. For example, the name on a definition statement defining a minor node must not be the major node name. A definition is active when VTAM® reads the major node in which it is contained (see Planning for NetView, NCP, and VTAM for NCP backup exceptions).

VTAM also creates internal resource definitions based on certain parameters in active VTAM definitions. For example, VTAM creates a direct attachment node (DAN) definition for each channel-attached non-SNA terminal in the VTAM domain when the device is activated. The name of the DAN is the character string coded on the CUADDR operand on the LOCAL macro that defines the terminal in a local non-SNA major node definition. Therefore, the name on a definition statement must not be the same as the CUADDR value specified on the LOCAL macro in a local non-SNA major node.

You should not use any name beginning with "IST", "IUT", or any of the following names for a major or minor node name:

VTAM
VTAMSEG
VTAMSG2
VTAMTERM

Note: VTAM may or may not police these names. Therefore, unpredictable results may occur. If, for example, the user codes IUTX0D00 as an application name, it will be accepted. If an attempt is made later to dynamically create TRLE IUTX0D00 for a TCP/IP CTC connection, the new definition will fail.

The names of major node members need to follow the rules for names detailed in Format of definition statements and Format of macroinstructions, except that they cannot contain the MVS™ system symbol delimiters, ampersand (&) or a period (.).