5 |
The identifier ª!º disables all tracing and should only be used by itself.
This command causes a diagnostic trace of the specified task or tasks to be displayed at the terminal where the TRACE command is invoked. This trace information shows each protocol exchange at the selected task and can be used by protocol experts to diagnose problems at the node or in a remote host.
The format of the display is the same at both the local and the remote terminal.
The TRACE command issued last, either locally or remotely, determines where the dis- play takes place.
Tracing of the Data Link layer (l) is not allowed if the TRACE command is issued at a re- mote terminal.
Caution
Enabling trace output has severe performance penalties for the communications software. This command should only be used in debugging problems. It should NEVERbe left enabled in operational nodes.
The trace output is enabled for only the tasks specified with the most recent TRACE command; trace output is disabled for all tasks not specified.
Trace output is generated by the selected tasks until either the TRACE command is is- sued again, to disable tracing or to select a new set of tasks, or the timeout specified for the TRACE command has expired. The command, TRACE, with no arguments, shows what tasks are currently printing trace information, the time remaining for an active trace, and the active len_ref value. The command, TRACE !, causes all tracing to be dis- abled.
Caution
Once trace has been initiated from a remote Station Manager, trace output continues to be sent to that remote Station Manager until terminated as described above. Trace output continues even if the remote Station Manager is disconnected or logged into another station. Be sure to stop your traces.
Detailing the interpretation of the trace data is beyond the scope of this document. It requires expertise in the internal operation of the TCP/IP protocols that is not needed by most users of the network.
A typical TRACE command is shown below:
= trace | i |
Trace enabled for: i | |
minutes | remaining = 10 |
len_ref | = 48 |
If you attempt a trace of the Data Link layer when it is not allowed, a response similar to the example above will be displayed, then followed by the message:
Trace not allowed for Data Link layer in remote mode.
TCP/IP Ethernet Communications User's Manual ± January 1996 |
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