Modify / Change DB_DOMAIN GLOBAL_NAME of the Database

Here We are going to change the DB_UNIQUE_NAME of the RAC database. Changing the Global Name doesn't need a database bounce but db_domain parameter needs database bounce.

**************************************** Step By Step Procedure ******************************************************

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# 1) Check Present Values
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SQL> sho parameter uniq
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_unique_name                       string      db01
SQL> sho parameter dom
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_domain                            string
SQL> select * from global_name;
GLOBAL_NAME
--------------------------------------------------------------------------------
db01

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 Here Domain Name is Set to Null, So Global Name just retrieves as db01
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# 2) check for the Database service
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PMON register the instance in the listener whenever a database comes to MOunt stage. Here we can see that LISTENER is listener to a service called "db01"

[oracle@host01 ~]$ lsnrctl  services | grep db01
Service "db01" has 1 instance(s).
  Instance "db011", status READY, has 1 handler(s) for this service...
Service "db01XDB" has 1 instance(s).
  Instance "db011", status READY, has 1 handler(s) for this service...
[oracle@host01 ~]$

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# 3) Modify Database Parameters
#########################################

Now we Will alter the DB_Domain Parameter in spfile as this is a STATIC parameter.

Alter system set db_domain="stepintooracledba.com" scope=spfile sid='*';

SQL> Alter system set db_domain="stepintooracledba.com" scope=spfile sid='*';
System altered.

Lets see Listener Status after Parameter change. Still it remains same.

oracle@host01 ~]$ lsnrctl services | grep db01
Service "db01" has 1 instance(s).
  Instance "db011", status READY, has 1 handler(s) for this service...
Service "db01XDB" has 1 instance(s).
  Instance "db011", status READY, has 1 handler(s) for this service...

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# 4) Shutdown / Startup Database
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[oracle@host01 ~]$ srvctl stop database -d db01

[oracle@host01 ~]$ srvctl start database -d db01

[oracle@host01 ~]$ lsnrctl services | grep db01
Service "db01.stepintooracledba.com" has 1 instance(s).
  Instance "db011", status READY, has 1 handler(s) for this service...
Service "db01XDB.stepintooracledba.com" has 1 instance(s).
  Instance "db011", status READY, has 1 handler(s) for this service...
[oracle@host01 ~]$ 

SQL> select * from global_name;

GLOBAL_NAME
--------------------------------------------------------------------------------
db01.stepintooracledba.com

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 Now We can See that PMON has registered the instance service name as "db01.stepintooracledba.com"
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 Comments Are Always welcome
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