.-NNSPREF--=--NONE----------------. >>-+---------------------------------+------------------------->< '-NNSPREF--=--network_node_server-'
- NNSPREF=NONE
- Specifies that dynamic switching of the network node server will
not be enabled.
If NNSPREF=NONE is specified through MODIFY VTAMOPTS, dynamic switching will be disabled. Existing CP-CP sessions with the current NNS will not be affected.
- NNSPREF=network_node_server
- Specifies the end node's preferred network node server. The name
specified can be fully qualified with a network ID. If the network
node server specified is not qualified with a network ID, the network
ID of the end node will be used as the default. By specifying this
start option with the name of a preferred network node server, the
EN will dynamically switch CP-CP sessions from its current network
node server to the preferred network node server when a CP-capable
physical link is activated with the preferred network node server.
In addition, when CP-capable links specified in the VTAM® configuration list are automatically activated at VTAM startup, only the link to the preferred network node server (if one exists) will trigger CP-CP session activation. If CP-CP sessions to the preferred network node server have not been initiated by the end of VTAM initialization, the network node server (NETSRVR) list will then be used to select a network node server.
This start option is modifiable using the MODIFY VTAMOPTS command. The network node specified for NNSPREF on the MODIFY VTAMOPTS command does not have to be predefined in the active network node server list and there does not have to be a nameless entry to handle it in the absence of an explicit entry. The value specified on the MODIFY command effectively gets dynamically added to the active NETSRVR list. This entry becomes the preferred entry and will have a higher priority than any other entry in the current NETSRVR list. The switching to the new preferred network node server will take place automatically if there is already an active CP-capable physical link to the new server.
Note: The switching could cause new session requests for resources on the EN to fail until the switching is complete.