The z/OS® Network File System uses trace facilities to record debug trace diagnostic information when a problem requires additional diagnostic information beyond diagnostic messages. Assuming that debug trace diagnostics were not activated at the time of the original failure, the problem must be recreated a second time and the NFS debug trace facilities turned on to capture the diagnostic information. The server provides debug trace diagnostic information from two separate trace facilities. The z/OS Network File System client provides debug trace diagnostic information from one trace facility.

The z/OS NFS server records z/OS NFS debug trace diagnostic information to the z/OS component trace buffer or to the server log data sets. z/OS NFS error and informational messages are also recorded to the z/OS component trace buffer or to the server log data sets. Only ERROR, WARN and INFO go into the log data set, depending on the server startup job setting. This setting may be ERROR, WARN (which includes ERROR), or INFO (which includes all three and is the default). All others are NOT written to the log, but all may be written in the component trace buffer. When recording debug trace diagnostic information, IBM® recommends that you set the component trace parameter according to performance tastes; "ALL" will cause the server to run more slowly and the defaults (ERROR + WARN + INFO + FFDC) will run faster. To record z/OS NFS server debug trace diagnostic information in the z/OS component trace buffer, see Using z/OS component tracing. To record z/OS NFS server debug trace diagnostic information in the log data sets, see z/OS NFS server debug trace capture.

The z/OS NFS client records z/OS NFS debug trace diagnostic information to the z/OS component trace buffer. z/OS NFS client error, informational, and warning messages are also recorded to the client log data sets. To record z/OS NFS client debug trace diagnostic information in the z/OS component trace buffer, see Using z/OS component tracing. To record z/OS NFS client error, informational, and warning messages in the log data sets, see z/OS NFS client debug trace capture.