Default values for background_file_dest,user_dump_dest in Oracle 12c on Linux

Oracle has introduced diagnostic_dest parameter with default value of $ORACLE_BASE. It's declared it changes the location of trace files of background and user processes (therefore, background_dump_dest and user_dump_dest are deprecated now). And despite of explicit settings of their values, the trace files are going to diagnostic_dest related directories (exception when instance is starting, one trace file of user process, participating in creating Oracle instance, is created in user_dump_dest directory).

It's not important at all (couse parameters are actually deprecated), but there are some little details that could explain settings of their default values.

The values are set the method similar with setting a value of audit_file_dest parameter (with little exception).

1. If the directory

$ORACLE_BASE/admin/$ORACLE_SID/bdump

or

$ORACLE_BASE/admin/$ORACLE_SID/udump

exist, the value of corresponding parameter is set to it.

2. If (1) is not true, then their value is set to

$ORACLE_HOME/rdbms/log

Shown above doesn't relate to Oracle 11g, where default values of these parameter linked to diagnostic_dest.

Good Luck !