How to check the diagnostic destination in Oracle

V$DIAG_INFO lists every ADR path Oracle uses for the current instance — alert log, trace directory, incident dumps, cdump, health monitor. Handy for locating log files without remembering the ADR hierarchy and for confirming ADR relocations.

SET LINESIZE 200
COLUMN name  FORMAT a30
COLUMN value FORMAT a110

SELECT * FROM v$diag_info;