Using NFS component trace PARMLIB members CTINFSnn and CTINFCnn

CTINFS00 and CTINFC00 members of SYS1.PARMLIB provide default component trace values for the z/OS NFS server and z/OS NFS client, respectively. These members are used automatically when the z/OS NFS application (the server or the client) is started. You can create and use additional copies of the member with different trace option values, placing them in SYS1.PARMLIB using the naming convention CTINFSnn /CTINFCnn.

Component tracing is active from the NFS application’s start with trace options defined in the CTINFSnn /CTINFCnn PARMLIB member, where nn=00 is the default. If the specified PARMLIB member is incorrect or absent, component tracing functions in minimum state (MIN) with a minimum set of trace options (FFDC and ERROR for the server, FFDC and MSG for the client). The operator can change trace options individually on the TRACE CT command, or can specify the name of a CTINFSnn /CTINFCnn PARMLIB member containing the desired trace options. Using a PARMLIB member on the TRACE CT command can help minimize operator intervention and avoid syntax or keystroke errors. The syntax and options for a z/OS NFS application component trace are shown in Starting component tracing for the z/OS NFS server and in Starting component tracing for the z/OS NFS client.

If the NFS client is started by z/OS UNIX (specified in the BPXPRMxx parmlib member), you can designate a component trace parmlib member with options to be used at startup. Use the CTRACE=nn parameter, as shown in the following example:

FILESYSTYPE TYPE(NFS) ENTRYPOINT(GFSCINIT) ASNAME(mvsnfsc)
PARM(‘INITD,CTRACE=nn’)

where:

mvsnfsc: is the name of the z/OS NFS procedure to be started.
nn: is the suffix of a CTINFCnn PARMLIB member.
CTRACE: must appear as the first or second parameter after INITD, in capital letters, separated by commas without blank spaces. If CTRACE=nn is not specified, the default PARMLIB member, CTINFC00, is used to initialize CTRACE for the client.

The component trace options specified on the CTINFxnn member control the component trace. These trace options can be overridden by a subsequent TRACE CT command if necessary, for example if a problem arises requiring a different set of trace options.

Note: The minimum trace options remain in effect after the TRACE CT,OFF,COMP=startup_name operator command, so tracing never stops while the server or the client is active.

The parmlib member used at NFS application’s startup specifies the size of the trace buffers to be used. Three buffers of that size are created and used cyclically. If no value is specified, or no parmlib member is found at startup, or syntax error is encountered while processing the parmlib member, and the dsps startup parameter is also not specified (for the server only), a default buffer size of 10 MB is used. The buffer size may be set in the range of 600KB to 600MB. The maximum value of 600MB was chosen because the total size of the three buffers must stay below 2 GB.

Note: The z/OS NFS applications do not support changing the buffer size after startup.

If no parmlib member is found at z/OS NFS application startup, or it does not contain a tracing Options specification, the trace options default to the MIN options setting (FFDC and ERROR for the server, FFDC and MSG for the client).

The CTINFxnn parmlib member contains the following parameters:

ON/OFF

specifies whether trace is turned on or off.

OPTIONS

specifies the trace options that are to be applied.

BUFSIZE(nnnnK | nnnnM)

specifies the size, in kilobytes (K) or megabytes (M), of one trace buffer. A valid range is from 600K to 600M.

WTRSTART(membername){WRAP|NOWRAP}

identifies a member containing source JCL for a started task that the system uses to start the component trace external writer and to open the data sets that the writer uses. You must also specify the WTR parameter.

WRAP or NOWRAP

If you specify WRAP, when the system reaches the end of the data set or group of data sets, it writes over the oldest data at the start of the data set or the start of the first data set. If you specify NOWRAP, the system stops writing to the data set or sets when the data set or sets are full.

If the WTRSTART parameter on the CTncccxx parmlib member or TRACE CT command specifies NOWRAP, the system uses the primary and secondary extents of the data set or sets. If the WTRSTART parameter specifies WRAP or omits the parameter, the system uses only the primary extent or extents.

Default: WRAP.

WTR(membername|DISCONNECT)

connects or disconnects the component trace external writer and the trace. The member name identifies the member that contains the source JCL that invokes the external writer. The membername in the WTR parameter must match the membername in the WTRSTART parameter.

WTR(DISCONNECT) disconnects the writer and the trace. The component continues tracing and placing the trace records in the address-space buffer, but stops passing trace records to the external writer.

You must also specify a WTRSTART or WTRSTOP parameter to start or stop the writer.