Steps for obtaining component trace data with an external writer
You can use an external writer to obtain component trace data for TCP/IP stacks, packet trace, OMPROUTE, and Telnet.
Procedure
Perform the following steps to obtain component trace data with an external writer:
- Enter the appropriate writer procedure in SYS1.PROCLIB,
as shown in the following example. Use a separate external writer
for each CTRACE component. You can have multiple procedures writing
to as many as 16 TRCOUT files either on disk or tape.
//PTTCP PROC //* REFER: SYS1.PROCLIB(PTTCP) //* COMPID: OPER //* DOC: THIS PROCEDURE IS THE IPCS CTRACE1 EXTERNAL WRITER PROCEDURE. //* USED BY TCP/IP . //* //IEFPROC EXEC PGM=ITTTRCWR,REGION=0K,TIME=1440 //* TIME=1440 to prevent S322 abends //TRCOUT01 DD DSNAME=MEGA.IPCS.CTRACE1,UNIT=SYSDA, // VOL=SER=STORGE, // SPACE=(4096,(100,10),,CONTIG),DISP=(NEW,CATLG), // DCB=(DSORG=PS) //
Restrictions:- Do not specify the DCB parameters RECFM, LRECL, and BLKSIZE. The external writer defaults to an optimal blocking factor.
- Do not specify the RLSE subparameter of the SPACE parameter. The output data sets are opened and closed more than once when GTF runs.
- Start the external writer using the following command:
TRACE CT,WTRSTART=procedure_name,WRAP
- Turn on the trace and connect the external writer to the
component either by specifying the external writer name in the PARMLIB
member, or by specifying the external writer name in the TRACE command.
When starting TCP/IP, because the SYSTCPDA component has no PARMLIB
member, the PARMLIB option is not applicable for SYSTCPDA. For example, TRACE CT,ON,COMP=SYSTCPDA,SUB=(TCPCS),PARM=CTIEZBDA is a
valid command. The PARMLIB member can specify a new buffer size or
the name or a writer. To turn the trace on and connect the external
writer to the component using a PARMLIB member, add the following
TRACEOPTS option to the PARMLIB member:
WTR(xxx)
where xxx is the procedure name of the external writer. Then use this PARMLIB member when starting the program (TCP/IP, OMPROUTE, TELNET, or the Resolver) or if the program is already executing, issue the following command:TRACE CT,ON,COMP=component_name,SUB=(procedure_name),PARM=parmlib_member
To turn on the trace and connect the external writer without using the PARMLIB member, enter the following command:TRACE CT,ON,COMP=component_name,SUB=(procedure_name)
When the system responds, enter the following command:R n,WTR=procedure_name,END
where n is the response number issued by the system. You can add options to the response. The options vary for each component name. See Formatting component traces for references to the component options.
- Use the DISPLAY command to check the external
writer status. Include a sublevel.
D TRACE,COMP=SYSTCPDA,SUB=(TCPCS2) IEE843I 11.33.06 TRACE DISPLAY 099 SYSTEM STATUS INFORMATION ST=(ON,0064K,00064K) AS=ON BR=OFF EX=ON MT=(ON,064K) TRACENAME ========= SYSTCPDA MODE BUFFER HEAD SUBS ===================== OFF HEAD 2 NO HEAD OPTIONS SUBTRACE MODE BUFFER HEAD SUBS -------------------------------------------------------------- TCPCS2 ON 0016M ASIDS *NONE* JOBNAMES *NONE* OPTIONS MINIMUM WRITER PTTCP
Tip: The external writer is active for packet and data. - Turn off the trace or disconnect the external writer. The
following two commands disconnect from the external writer, while
leaving the trace running internally.
TRACE CT,ON,COMP=component_name,SUB=(procedure_jobname)
When the system responds, enter the second command:R nn,WTR=DISCONNECT,END
- Stop the external writer using the following command:
TRACE CT,WTRSTOP=procedure_name
Parent topic: Modifying options with the TRACE CT command