SNAX/XF and SNAX/APN Configuration and Management Manual

SCF Commands for SNAX/XF and SNAX/APN
SNAX/XF and SNAX/APN Configuration and Management Manual—425836-006
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TRACE Command
PTrace to collect the minimum amount of useful information for display, you must
specify a RECSIZE of at least 100 bytes.
In addition, internal trace records for the service manager capture all called procedures
and sub-procedures in their order of invocation. These records are very important to
HP support and development personnel in problem determination. For a SUBSYS
(service manager) trace, RECSIZE must be at least 80 bytes to allow this internal trace
data to be collected.
HP recommends specifying a RECSIZE much larger than these minimum values. How
large depends on the problem, the types of records collected, and the size of your data
records. Trace records are variable length (not fixed length), so that disk space and
extended data segment space are not wasted if a trace record is smaller than
RECSIZE.
For service-manager traces, the largest records are usually requests by, and
responses to, the SPI interface (through SCF or user-written management programs).
These trace records can often be several thousand bytes long. If the trace records are
truncated, token values and other necessary information cannot be determined.
Therefore, if it is important that all the SPI information be captured, you should use the
maximum allowed value for this option.
For line traces, it is desirable that RECSIZE be large enough to capture all the data
received from and sent to applications as well as all the data in BIU in/out and PIU
in/out type records, plus the trace-record headers. In general, RECSIZE should be 50
bytes larger than the largest buffer size used in the application’s file-system requests
(READ, WRITE, WRITEREAD, and so on).
Minimally, RECSIZE should be at least 50 bytes larger than the line’s RECSIZE (as
specified in the ADD LINE or ALTER LINE command), so that PIU in/out type records
can be fully captured.
If your data is security-sensitive, it may not be desirable to trace the request/response
unit (RU) in BIU and PIU data records. RECSIZE should, however, be large enough so
that the transmission header (TH) and request/response header (RH) can be
displayed.
SELECT
There are two general types of trace records: external trace records, which display
what occurred (for example, the data sent to a line); and internal trace records, which
display how and why it occurred (for example, the routines that were invoked or the
internal states of objects). For HP support and development personnel, both types are
important in problem determination.
Therefore, for the service manager, SELECT ALL is recommended.
For LINE objects, SELECT LINESTD is recommended; this option traces the upper
SNA layers, excluding levels 1 and 2. This selection will significantly reduce the
number of records traced. If, however, you suspect a link-level problem (such as a