Problem Diagnosis - Expert Oracle RAC Performance Diagnostics and Tuning - page 613

ADR Configuration
An ADR base is the base directory identified during Oracle database installation (in prior versions of Oracle, this
directory was identified as the admin directory). Because Oracle uses the ADR to store diagnostic information
related to multiple products and components, there are several ADR homes: one for each component. All ADR
homes are grouped under the ADR base directory and are identified by the parameter DIAGNOSTIC_DEST. In a RAC
environment, each instance will have a separate base directory:
SQL> show parameter diagnostic_dest
NAME TYPE VALUE
------------------------------------ ----------- ------------------
diagnostic_dest string /app/oracle
From the same ADR base, ADR can support multiple homes and is managed by how many products are
configured on the server. In the output following, there are several homes: one for ASM, another for the database, and
the others for the LISTENER :
adrci> show homes
ADR Homes:
diag/asm/+asm/+ASM1
diag/rdbms/prddb/PRODDB_1
diag/tnslsnr/prddb1/listener_scan3
diag/tnslsnr/prddb1/listener
diag/tnslsnr/prddb1/listener_scan1
diag/tnslsnr/prddb1/listener_scan2
ADR is enabled by default and the different ADR destination homes can be identified by querying the view
V$DIAG_INFO :
Script Name: MVRACPDnTap_ADRDiagInfo.sql
SELECT INST_ID INT, NAME, VALUE
FROM GV$DIAG_INFO
ORDER BY INST_ID, NAME;
In NAME VALUE
--- ------------------------ ------------------------------------------------
1 ADR Base /app/oracle
ADR Home /app/oracle/diag/rdbms/prddb/PRDDB_1
Active Incident Count 3
Active Problem Count 2
Diag Alert /app/oracle/diag/rdbms/prddb/PRDDB_1/alert
Diag Cdump /app/oracle/diag/rdbms/prddb/PRDDB_1/cdump
Diag Enabled TRUE
Diag Incident /app/oracle/diag/rdbms/prddb/PRDDB_1/incident
Diag Trace /app/oracle/diag/rdbms/prddb/PRDDB_1/trace
Health Monitor /app/oracle/diag/rdbms/prddb/PRDDB_1/hm
..... . . . . . .
. . . . . . . .
5 ADR Base /app/oracle
ADR Home /app/oracle/diag/rdbms/prddb/PRDDB_5
Active Incident Count 37
Active Problem Count 6
Diag Alert /app/oracle/diag/rdbms/prddb/PRDDB_5/alert