How a link station is activated

Each cross-subarea link station is uniquely activated in the following ways:

For channel link stations adjacent to an NCP, there are two methods of activation:
- If a link station has been defined and named by VTAM®, it can be activated only automatically. Any VARY ACT command specifying a channel link station is rejected. However, these channel link stations can be deactivated directly, indirectly (by halting VTAM), or automatically.
- If the link station has been defined and named by the user (with a PU definition statement), it can be activated by the VARY ACT command.
Channel link stations adjacent to another host processor can be activated only directly or indirectly, and can be deactivated with VARY commands. These channel link stations are named in the definition for the channel-attachment major node.
SDLC, LAN, and X.25 link stations are activated directly or indirectly with the VARY ACT command.

When a cross-subarea link station becomes active, VTAM issues a message to the operator indicating the name and subarea number of the adjacent subarea node with which contact has been established.