You can specify the link stations that are to be automatically activated using the CUADDR and RNAME operands on the PCCU definition statement for the NCP. (This method is recommended to simplify operating procedures and reduce the chance for operator error.) If you do not specify these link stations, or if you need to override the defined link station names, you can use the U or RNAME operands (or both) on the VARY ACT command when activating the NCP.

When the NCP is activated, the specified link stations and their associated links are automatically activated if they are not already active. If any of these link stations are not yet known to VTAM® (because the NCP to which they are subordinate has not been activated), VTAM remembers them until they become known (through the activation of their major node). Then VTAM completes the activation. VTAM informs you of the link stations that are awaiting the activation of their NCP.

When activating a link in a channel-attachment major node, the operator needs to supply the channel device name of the link unless it is supplied in the LINE definition statement. The operator can also specify the channel device name to override the value in the LINE definition. To supply the channel device name, use the U operand of the VARY ACT command when activating the link.

If VTAM needs the operator's assistance to create a connection for a link in a channel-attachment major node, VTAM displays a message indicating that a connection request is denied because the link is not physically attached or is unknown to the operating system. In either case, the link must be available before the channel-attachment major node can be activated.