-- DATABASE IS OPEN
COLUMN INST_ID FORMAT 9999 HEADING 'INST_ID'
COLUMN CON_ID FORMAT 9999 HEADING 'CON_ID'
COLUMN VALUE FORMAT A50 WRAP HEADING 'VALUE'
SELECT INST_ID, CON_ID, VALUE FROM v$diag_info WHERE NAME = 'Diag Trace';


INST_ID CON_ID VALUE                                             
------- ------ --------------------------------------------------
      1      0 /opt/oradb/diag/rdbms/XXX/XXX/trace     

-- DATABASE IS CLOSE
[oracle@srv ~]$ adrci
ADRCI: Release 19.0.0.0.0 - Production on Wed Jul 3 18:07:37 2024
Copyright (c) 1982, 2019, Oracle and/or its affiliates.  All rights reserved.
ADR base = "/u01/app/oracle"

adrci> SHOW HOMES
ADR Homes:
diag/rdbms/oradb/oradb
diag/tnslsnr/srv/listener

adrci> exit

[oracle@srv ~]$ cd /u01/app/oracle/diag/rdbms/oradb/oradb/trace

[oracle@srv trace]$ ls -ltr alert*
-rw-r----- 1 oracle oinstall 215280 Jul  3 17:59 alert_oradb.log

[oracle@srv trace]$ cat alert_oradb.log
[oracle@srv trace]$ more alert_oradb.log
[oracle@srv trace]$ less alert_oradb.log
# OR,
[oracle@srv trace]$ tail -100f alert_oradb.log

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