SNA Link/iX Node Managers Guide (30291-90009)

110 Chapter5
SNA Link Troubleshooting
The Logging Facility
The Logging Facility
Logging records subsystem events — significant normal events, as well
as error events — for use in problem determination and monitoring
network usage and resources. NMS performs SNA link logging| at two
levels: for the SNA network (SNA Transport logging), and at link level
(SDLC link logging, X.25 link logging, token ring link logging, and link
trace logging). SNA link logging is configured through NMMGR (see
Chapter 3 , “Logging Configuration,” of this manual).
When you configure SNA link logging, you indicate the level you want
logging configured for by specifying the level’s subsystem number.
Then, within each subsystem, you can indicate which events you want
logged, by specifying event class numbers. Each type of SNA link
logging is described below.
SNA Transport Logging
SNA Transport logging records the usage of the communications
network resources, and serves as a tool in resolving network problems.
It is controlled through the MPE commands SHOWNMLOG, SWITCHNMLOG,
and RESUMENMLOG. These commands enable the node manager to
determine the number of and available space in the current NM log file
(NMLG
nnnn .PUB.SYS, where nnnn is a number from 0000 through 9999),
close the current NM log file and open a new one, and activate logging
after a recoverable error. The MPE commands are described in Chapter
6 , “MPE Commands,” of this manual.
The NM log file can be formatted through the NMDUMP utility. Using
NMDUMP for SNA Transport (including an example of the SNA
Transport logging format) is described later in this chapter.
More-detailed information about NMDUMP is contained in Using the
Node Management Services Utilities.
The logging subsystem number for SNA Transport is SUB0001, and
these are the class numbers:
• CLAS0010: node events
— Node activation
— Link activation
— Link errors
— Internal errors
— Node shutdown
• CLAS0011: protocol errors
— Packet discards/rejects