Database Links using Autonomous Database with private endpoints across regions

I am using Autonomous Databases 19c shared infrastructure(ADB-S) with the source in Phoenix and the target in London.

Prereqs include:

• Two ADB-S with private endpoints , one in each region
• Region peering configured
• DNS configured -- I like to create a compute VM in each region and verify region peering and DNS is working

Once the above is completed follow the next steps to create the db links.

• Upload the target database wallet to object storage
• Create the directory in the database to hold the wallet in the source database
• Create the credential to access object storage in the source database
• Copy the wallet from object storage to the source database
• Create another credential to access target database in the source database
• Create the database link

References:

• Creating Database Links from Autonomous Database to Databases with Private Endpoints
• VCN Peering for ADBs with Private Endpoints and Cross-Region Autonomous Data Guard
• Private DNS Implementation

Example:

Run the following commands  on the source database:

create directory wallet_dir_london as 'WALLETDIR_LONDON';

begin

    DBMS_CLOUD.create_credential (

    credential_name => 'OBJ_STORE_CREDA',

    username => 'YOUROCIUSERNAME',

    password => 'YOURTOKEN

  ) ;

end;

/

begin DBMS_CLOUD.GET_OBJECT(

      credential_name => 'OBJ_STORE_CREDA',

      object_uri => 'https://objectstorage.us-phoenix-1.oraclecloud.com/n/YOURTENANCY/b/gfswinglondon/o/cwallet.sso',

      directory_name => 'WALLET_DIR_LONDON'); 

      END;

 /  

SELECT * FROM DBMS_CLOUD.LIST_FILES('WALLET_DIR_LONDON');

BEGIN

   DBMS_CLOUD.CREATE_CREDENTIAL(

   credential_name => 'DB_LINK_CRED',

   username => 'ADMIN',

   password => 'YOURADBPASSWORD');

END;

/

SELECT owner, credential_name FROM dba_credentials

BEGIN

DBMS_CLOUD_ADMIN.CREATE_DATABASE_LINK(

    db_link_name => 'LONDONDBLINK', 

    hostname => '*********.adb.uk-london-1.oraclecloud.com',    (your hostname here)

    port => '1522',

   service_name => '**************_gfswinglon_high.adb.oraclecloud.com',   (your service name here)

   ssl_server_cert_dn => 'CN=adwc.eucom-central-1.oraclecloud.com, OU=Oracle BMCS FRANKFURT, O=Oracle Corporation, L=Redwood City, ST=California, C=US',

   credential_name => 'DB_LINK_CRED',

   directory_name => 'WALLET_DIR_LONDON',

   private_target => TRUE);

END;

/

select ora_database_name@londondblink from dual;