Creating an Oracle Database 12c on Grid Infrastructure (Silent DBCA Method)

Assumptions

This instruction assumes:

• Oracle Linux 6.x or 7.x (x86_64) is installed and operational
• Grid Infrastructure 12c (12.1.0.2) is installed and running with Oracle Restart
• The ASM instance is running with +DATA and +RECO diskgroups created and mounted
• Oracle Database 12.1.0.2 software is installed (software-only) in /u01/app/oracle/product/12.1.0.2/db_1
• The Grid Infrastructure home is a separate directory from the database home
• The oracle user exists and belongs to oinstall, dba, oper, backupdba, dgdba, and kmdba groups
• The Grid Infrastructure listener (LISTENER) is running on port 1521
• The server has at least 21 GB of available memory for SGA (15 GB) + PGA (6 GB)
• The +DATA diskgroup has at least 15 GB of free space
• The +RECO diskgroup has sufficient free space for the Fast Recovery Area
• Root access is available for /dev/shm resizing if needed
• This is a traditional single-instance database

Prerequisites

Verify Grid Infrastructure and configure environment

All verification commands run as the oracle user unless noted otherwise.

1. Verify Oracle Restart is running

crsctl check has

Expected output:

CRS-4638: Oracle High Availability Services is online

2. Verify the ASM instance is running

srvctl status asm

Expected output:

ASM is running on {HOSTNAME}

{HOSTNAME} -- the server hostname where Grid Infrastructure is installed. This placeholder appears throughout the document in expected output examples.

3. Verify diskgroups are mounted

Note: asmcmd is a Grid Infrastructure utility. If your PATH points to the database home, use the full path: $GRID_HOME/bin/asmcmd (where $GRID_HOME is the Grid Infrastructure home directory).

asmcmd lsdg

Expected output:

State    Type    Rebal  Sector  Block  AU   Total_MB  Free_MB  Req_mir_free_MB  Usable_file_MB  Offline_disks  Voting_files  Name
MOUNTED  EXTERN  N      512     4096   4194304  ...     ...      0                ...             0              N             DATA/
MOUNTED  EXTERN  N      512     4096   4194304  ...     ...      0                ...             0              N             RECO/

Both +DATA and +RECO must show MOUNTED in the State column. Confirm Free_MB for +DATA is at least 15000.

4. Verify the listener is running

srvctl status listener

Expected output:

Listener LISTENER is enabled
Listener LISTENER is running on node(s): {HOSTNAME}

5. Verify the oracle user group membership

id oracle

Expected output:

uid=54321(oracle) gid=54321(oinstall) groups=54321(oinstall),54322(dba),54323(oper),54324(backupdba),54325(dgdba),54326(kmdba)

Confirm that oinstall and dba groups are present.

Set environment variables

6. Configure the oracle user environment

The environment must point to the database home, not the Grid Infrastructure home. As the oracle user, create the scripts directory and environment script:

mkdir -p /home/oracle/scripts
cat > /home/oracle/scripts/setEnv.sh <<'EOF'
export ORACLE_BASE=/u01/app/oracle
export ORACLE_HOME=$ORACLE_BASE/product/12.1.0.2/db_1
export ORACLE_SID={DB_NAME}
export PATH=$ORACLE_HOME/bin:$PATH
export LD_LIBRARY_PATH=$ORACLE_HOME/lib:/lib:/usr/lib
EOF

{DB_NAME} -- the database name and SID (e.g., ORCL). Use uppercase, 8 characters or fewer.

Source the environment:

grep -qxF '. /home/oracle/scripts/setEnv.sh' /home/oracle/.bash_profile || echo '. /home/oracle/scripts/setEnv.sh' >> /home/oracle/.bash_profile
source /home/oracle/.bash_profile

Verify:

echo $ORACLE_HOME

Expected output:

/u01/app/oracle/product/12.1.0.2/db_1

7. Verify the DBCA template exists

ls $ORACLE_HOME/assistants/dbca/templates/General_Purpose.dbc

Expected output:

/u01/app/oracle/product/12.1.0.2/db_1/assistants/dbca/templates/General_Purpose.dbc

Verify /dev/shm

8. Verify /dev/shm is sized for the SGA

The tmpfs mount at /dev/shm must be at least as large as the SGA. With a 15 GB SGA target, /dev/shm must be at least 15 GB.

df -h /dev/shm

Expected output:

Filesystem      Size  Used Avail Use% Mounted on
tmpfs            16G     0   16G   0% /dev/shm

If the Size column shows less than 15 GB, resize it as root:

mount -o remount,size=16G /dev/shm

Make the change persistent by editing /etc/fstab as root. Ensure the tmpfs entry reads:

tmpfs  /dev/shm  tmpfs  defaults,size=16G  0  0

Database Creation

Step 1: Suppress shell history recording

Warning: The DBCA command includes passwords on the command line. These will be visible in ps output while the command runs and in shell history after completion. Suppress history recording before executing the command.

As the oracle user:

unset HISTFILE

Step 2: Run DBCA in silent mode

Warning: The -characterSet AL32UTF8 parameter sets the database character set permanently. This cannot be changed after database creation.

Run the following command as the oracle user. Replace {DB_NAME}, {SYS_PASSWORD}, and {SYSTEM_PASSWORD} with your values. {DB_NAME} must match the ORACLE_SID set in the environment.

{SYS_PASSWORD} -- password for the SYS account. Minimum 8 characters, must include uppercase, lowercase, and a digit. Avoid special characters that require shell escaping (!, $, `, \, ", '). If special characters are required, enclose the password in single quotes on the command line.

{SYSTEM_PASSWORD} -- password for the SYSTEM account. Same requirements as SYS.

dbca -silent -createDatabase \
  -templateName General_Purpose.dbc \
  -gdbname {DB_NAME} \
  -sid {DB_NAME} \
  -sysPassword {SYS_PASSWORD} \
  -systemPassword {SYSTEM_PASSWORD} \
  -storageType ASM \
  -diskGroupName +DATA \
  -recoveryAreaDestination +RECO \
  -recoveryAreaSize 50000 \
  -characterSet AL32UTF8 \
  -nationalCharacterSet AL16UTF16 \
  -automaticMemoryManagement false \
  -initParams "memory_target=0,sga_target=15G,sga_max_size=16G,pga_aggregate_target=6G" \
  -databaseType MULTIPURPOSE \
  -emConfiguration NONE \
  -listeners LISTENER \
  -responseFile NO_VALUE

Parameter notes:

• -storageType ASM and -diskGroupName +DATA place all data files on the +DATA diskgroup.
• -recoveryAreaDestination +RECO sets the Fast Recovery Area to the +RECO diskgroup. -recoveryAreaSize 50000 allocates approximately 50 GB for the recovery area.
• -automaticMemoryManagement false disables AMM. On Linux with more than 4 GB of RAM, AMM is not supported — ASMM is used instead.
• -initParams sets memory sizing: sga_target=15G, sga_max_size=16G (allows 1 GB growth without restart), pga_aggregate_target=6G, and memory_target=0 (confirms AMM is disabled).
• -nationalCharacterSet AL16UTF16 is the default national character set. If DBCA does not recognize this as a command-line parameter, the General_Purpose.dbc template uses AL16UTF16 by default.
• -listeners LISTENER registers the database with the existing Grid Infrastructure listener named LISTENER.
• -responseFile NO_VALUE indicates all parameters are specified on the command line.
• DBCA automatically registers the database with Oracle Restart. No manual srvctl add database is needed.

Database creation takes 10-30 minutes depending on hardware.

Expected output:

Copying database files
1% complete
2% complete
...
Creating and starting Oracle instance
...
40% complete
...
Completing Database Creation
...
100% complete
Look at the log file "/u01/app/oracle/cfgtoollogs/dbca/{DB_NAME}/{DB_NAME}.log" for further details.

Step 3: Verify the DBCA log

Check the DBCA log for errors. This log captures all actions DBCA performed during database creation:

tail -20 /u01/app/oracle/cfgtoollogs/dbca/${ORACLE_SID}/${ORACLE_SID}.log

The log should end without ORA- errors. Informational messages about Enterprise Manager configuration being skipped (NONE) are expected.

Validation

Quick check

srvctl status database -d ${ORACLE_SID}

Expected output:

Database {DB_NAME} is running

Full validation

1. Verify Oracle Restart registration

srvctl config database -d ${ORACLE_SID}

Expected output:

Database unique name: {DB_NAME}
Database name: {DB_NAME}
Oracle home: /u01/app/oracle/product/12.1.0.2/db_1
Oracle user: oracle
Spfile: +DATA/{DB_NAME}/PARAMETERFILE/spfile{DB_NAME}.ora
...
Database role: PRIMARY
Start options: open
Stop options: immediate
...

Confirm Oracle home points to the database home and Spfile is on +DATA.

2. Verify database version

sqlplus -s / as sysdba <<'EOF'
SELECT banner FROM v$version WHERE ROWNUM = 1;
EXIT;
EOF

Expected output:

BANNER
--------------------------------------------------------------------------------
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production

3. Verify database open mode

sqlplus -s / as sysdba <<'EOF'
SELECT name, open_mode FROM v$database;
EXIT;
EOF

Expected output:

NAME      OPEN_MODE
--------- --------------------
{DB_NAME} READ WRITE

4. Verify memory parameters

sqlplus -s / as sysdba <<'EOF'
SHOW PARAMETER sga_target;
SHOW PARAMETER sga_max_size;
SHOW PARAMETER pga_aggregate_target;
SHOW PARAMETER memory_target;
EXIT;
EOF

Expected output:

NAME                  TYPE        VALUE
--------------------- ----------- -----
sga_target            big integer 15G

NAME                  TYPE        VALUE
--------------------- ----------- -----
sga_max_size          big integer 16G

NAME                  TYPE        VALUE
--------------------- ----------- -----
pga_aggregate_target  big integer 6G

NAME                  TYPE        VALUE
--------------------- ----------- -----
memory_target         big integer 0

memory_target=0 confirms Automatic Memory Management is disabled. sga_target=15G and pga_aggregate_target=6G confirm ASMM is active.

5. Verify character set

sqlplus -s / as sysdba <<'EOF'
SELECT value FROM nls_database_parameters WHERE parameter = 'NLS_CHARACTERSET';
SELECT value FROM nls_database_parameters WHERE parameter = 'NLS_NCHAR_CHARACTERSET';
EXIT;
EOF

Expected output:

VALUE
----------------------------------------
AL32UTF8

VALUE
----------------------------------------
AL16UTF16

6. Verify data files are on +DATA

sqlplus -s / as sysdba <<'EOF'
SELECT name FROM v$datafile;
EXIT;
EOF

Expected output:

NAME
----------------------------------------------------------------------
+DATA/{DB_NAME}/datafile/system.258.1234567891
+DATA/{DB_NAME}/datafile/sysaux.259.1234567893
+DATA/{DB_NAME}/datafile/undotbs1.260.1234567895
+DATA/{DB_NAME}/datafile/users.261.1234567897

All data files must be on +DATA.

7. Verify recovery area is on +RECO

sqlplus -s / as sysdba <<'EOF'
SELECT name, space_limit/1024/1024 AS limit_mb, space_used/1024/1024 AS used_mb FROM v$recovery_file_dest;
EXIT;
EOF

Expected output:

NAME        LIMIT_MB    USED_MB
----------- ----------- -----------
+RECO       50000       ...

8. Verify listener registration

lsnrctl status

Expected output (relevant section):

...
Services Summary...
Service "{DB_NAME}" has 1 instance(s).
  Instance "{DB_NAME}", status READY, has 1 handler(s) for this service...
Service "{DB_NAME}XDB" has 1 instance(s).
  Instance "{DB_NAME}", status READY, has 1 handler(s) for this service...
The command completed successfully

Troubleshooting

References

• Oracle 12.1 Administrator's Guide - Creating and Configuring a Database
• Oracle 12.1 Administrator's Guide - Managing Memory
• Oracle 12.1 Installation Guide - Using Response Files
• Oracle 12.1 Real Application Clusters Installation Guide - Using Scripts or Response Files
• ORACLE-BASE - DBCA Silent Mode