I don't know how many of you have traced sql.. It can be helpful to try to find out why an error is occuring or just verifying parameters (like DEFAULT_SDU_SIZE).
The way to accomplish this is to
1) create a new subdirectory in /tmp
2) Copy the files from $ORACLE_HOME/network/admin to /tmp/{mydir}
3) Set TNS_ADMIN to /tmp/{mydir}
4) Put these lines in the sql.ora
TRACE_DIRECTORY_CLIENT = /tmp/{mydir}
TRACE_LEVEL_CLIENT = 16
trace_unique_client = on
Well in 11g, and the introduction of ADR, the trace file does NOT go to /tmp/{mydir} like it used to... it goes to
$ORACLE_BASE/diag/clients/user_oracle/host_xxx/trace
The only way to override this is to put in
DIAG_ADR_ENABLED=off
here is a link that helped
http://el-caro.blogspot.com/2008/07/11g ... files.html