Maintenance

To support the maintenance of host-based X.25 connections, the Terminal Diagnostic Support Monitor (TermDSM) utility supports additional command functions. These functions are part of the DIag, DUmp, Reset, and Status commands (capital letters indicate command abbreviations). Additionally, the TermDSM Trace command allows tracing of X.25 level 2 or level 3, or of a virtual circuit (VC).

Several of the TermDSM command functions now provide data about DTC/X.25 Network Access cards in addition to the data they provide about asynchronous cards. For example, the Diag Selftest function tests DTC/X.25 Network Access cards (SNPs) as well as asynchronous cards (SICs).

Terminology

TermDSM uses designations for the types of cards it tests that you might not be familiar with. Asynchronous cards are referred to as SICs, or serial interface cards. Likewise, DTC/X.25 Network Access cards are referred to as SNPs. SNP is an abbreviation for synchronous network processor.

A number of the TermDSM commands use the SNP designation as a subcommand. For example, to capture information about a specific DTC/X.25 Network Access card and write it to a file you would enter the DUmp command in TermDSM, then enter the SNp subcommand, specifying the DTC number and card number as the SNp parameters.

Trace Command Options

The trace function has been added to TermDSM so that X.25 packets can be traced at the DTC and card level.

Only one trace (and one trace option) can be active at a time.

To enable tracing you enter the TermDSM Trace command then choose a trace option through the TRACEON subcommand. Each of the three trace options are described. Depending on the trace level you specify, you will then be prompted for additional information.

VC Trace

If you choose trace option 1, VC trace, you will be prompted for a VC (virtual circuit) number. Enter the number of the VC for which you want trace information. You will then be asked to specify a filter for the trace. You can choose either to trace headers only or to trace full packets. You will also be given the option of specifying a filename for the trace file.

Level 2 Trace

If you choose trace option 2, level 2 trace, you will be prompted for the filter (trace headers only or full packets) and given the option of specifying a file name. No other information is required.

Level 3 Trace

If you choose trace option 3, level 3 trace, you will be prompted for a VC type. Possible responses are PAd, to trace only PAD VCs, SYs, to trace system-to-system VCs, or All, to trace both PAD and system-to-system VCs that are active through the designated DTC and card. You will also need to specify the link name of the X.25 link. You will then be prompted for the filter (trace headers only or full packets) and given the option of specifying a file name.

For a complete description of TermDSM and its use with all DTC connection card options, see Troubleshooting Terminal, Printer, and Serial Device Connections manual.

Trace Formatting

The trace file can be formatted with the NMDUMP utility. Enter option 2 at the prompt "Would you like to format a log or trace file" then select subsystem ID 60 for DTC/X.25 Link. For more information, refer to Using the Node Management Services (NMS) Utilities manual.

Logging

Logging for host-based X.25 links is enabled and disabled in the NMMGR configuration file, as is the case for other link products. However, host-based X.25 log files are formatted through a tool called EVLOG (you cannot use the NMDUMP formatter for host-based log files). See Chapter 8 “Formatting Host-Based X.25 Log Files” for instructions on using the EVLOG formatter.

Event Log Files

Events are logged to two alternating log files for each DTC. When you bring the DTC up, it immediately begins logging to the first log file. The DTC records events to that file until too few bytes are available for the next log record entry. At this point, the DTC begins recording to the second log file. Alternating log files in this manner assures that at least five hundred records are always available for formatting and evaluation.

Log File Name Format

The format of the log file names is as follows:

HnnnnnnA.PUB.SYS: (first log file)
HnnnnnnB.PUB.SYS: (second log file)

All the host-based X.25 log files begin with the letter H. The second through the seventh digits correspond to the last six digits of the DTC address (remember, each DTC has its own set of two log files). The A or B at the end of the file name indicates whether it is the first or the second file.

Each file stores up to 500 records, with each record or packet being 132 bytes.

Hewlett-Packard recommends that you treat the files as read-only files. Once you have information that you want to format, copy the log file to another filename and format that file with the EVLOG formatter.




	NOTE: Switching to a different file only occurs when the current file runs out of space. If you are concerned about limiting the number of records written and formatted, a timestamp filtering capability is available in the formatter.