# Creating a log file for dectrace

dectrace reads the log file created by oammon (agpierror.log). By default, this file does not contain NMS ISDN protocol stack messages. To enable oammon to log messages from the stack, use either (or both) of the following utilities:

Utility | Description
agtrace | agtrace takes, as parameters: A bit mask The board number (default 0) The channel number (default 0) To trace the NMS ISDN protocol stack, set the 0x80000 bit. To enable oammon to display and log the trace, use the -f option.
itrace | The ISDN stack includes many entities (for example, layer 1 entities, layer 2 entities, layer 3 entities, management entities, timer entities) that send debug messages to oammon. itrace limits the number of ISDN entities that send debug messages to oammon (by default all the entities are enabled). itrace takes as arguments a flag (on or off), board number, NAI number, and a list of entities (from the file isdntype.h). An exclamation point (!) before the entity list enables the sending of buffers along with the messages. For example, to prepare an agpierror.log for board 0, NAI 1, containing Q.931 buffers, enter the following information: agtrace 801000 0 itrace off 0 1 * itrace on 0 1 !Dd and run the application. To prepare an agpierror.log for board 0, NAI 1, containing only ACU messages, enter the following information: agtrace 801000 0 itrace off 0 1* itrace on 0 1 AC and run the application.

The log file is located in the following directory:

Operating system | Directory
--- | ---
Windows | nms\oam\log
UNIX | /var/opt/nms/ag

Tracing is not recommended when performing heavy load tests. The high number of accesses to the log file caused by tracing can dramatically decrease the coprocessor's capability to handle the messages.

Embedded errors in agpierror.log may not be handled correctly by dectrace during load tests, or if you do not follow the indications about limiting the number of messages or buffers sent to the board monitoring utility.

When reporting a potential problem in the NMS ISDN stack, include the entire agpierror.log file. Do not use itrace in this case, and do not include the output of dectrace.