When the Node Manager software is posted to PC 3 and PC 5, and when •bad", •orphan", and/or •trace" packet processing is properly enabled, they are logged to system LU 1 (system console) and to the event log file (EL.TXT) if it exists.

Note

Node Manager software does not process Group DSAP (GDSAP) packets. Recall from Chapter 2, a GDSAP packet contains a •1" in the least significant bit position of the DSAP field (that is, an odd DSAP is interpreted as a Group DSAP). For packets with odd DSAPs, the driver retrieves the class number posted to Program Code 7, and queues the packet on that class number. To process GDSAP packets, a user"written routine is required.

Note

On recognition of a •bad", •orphan", or •trace" packet, the driver is internally programmed to access class numbers associated with Program Codes 3 and 5 as applicable. However, Program Codes 1 and 9 are used for storing class numbers of a Network Management Dispatcher program and VCP server routine, respectively. These Program Codes may be accessed by the driver only if the driver is externally programmed to do so through the proper driver request. (A Dispatcher program is needed as an intermediate packet router for the simultaneous operation of a user"written VCP server routine and Node Manager software. Incoming VCP server packets and Node Manager packets are routed by the driver to the same SAP, F8 hex.)

Saving Orphan Packets

Orphan packets are those packets received that are not deliverable to a program or process. In other words, an orphan packet contains a DSAP for which there is no, or an invalid, class number in the driver's class table.

In the default case, the LANIC card and driver will discard orphan packets. When configured to save orphans, the LANIC card and driver will send them to the program whose class number is posted to Program Code 3 in the driver's class table. If this program is the Node Manager software, orphan packets are logged to system LU 1 (system console) and to the event log file associated with the card.

Although it processes orphans, Node Manager software does not configure the card and driver to save orphans. In addition, it does not detect whether saving orphans is configured.

To configure saving orphans, a Device Control request is made interactively from the Command Interpreter prompt (CI>):

CI> CN,User_LU,45B,x

4%10 Node Manager Operations