Donald K. Burleson

Oracle and Expert Systems Technology

Oracle - Standard Oracle Log and Trace Files

As we know from previous lessons, the location of Oracle's database trace and dump files are determined by parameters within the init.ora file.  The easiest way to know the location of Oracle's trace and dump files is to use the server manager utility.  As we see below, server manager can be used to display all of the dump parameters.  These same parameters are used in the init.ora file to define the log and trace options.

NAME                                TYPE    VALUE
----------------------------------- ------- ------------------------------
background_core_dump                string  full                         
background_dump_dest                string  ?/rdbms/log
core_dump_dest                      string  ?/dbs
max_dump_file_size                  string  10240                        
shadow_core_dump                    string  full                          user_dump_dest                      string  ?/rdbms/log

Note that the parameters that are suffixed with "dest" tell us where the files are located. In the example above we see that the background_dump_dest and the user_dump_dest are both set to $ORACLE_HOME/rdbms/log.  If we go to this directory, we will find a host of different alert and trace files:

Also note that the Oracle alert log is located in the background_dump_dest directory.  Here we see the main log for the fred database, called alert_fred.log.  The alert log will contain all relevant Oracle messages, including startup and shutdown messages, as well as redo log switches and serious errors.

For each trace file in the directory, we see that they are prefixed by the main process that spawned the error.  We see traces for the process monitor process (pmon), the Recoverer process (reco), the log writer (lgwr), the database writer (dbwr), and the system monitor process (smon).  Generic Oracle trace file are always prefixed with "ora".


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