1. Download the global service manager software from edelivery.oracle.com and unzip.

   Figure 3-1 Oracle Software Delivery Cloud

   
2. Start Oracle Universal Installer from the root directory of the software media and follow the prompts.

   When the installation completes, the global service manager home directory contains binaries required to run the global service manager and the Global Service Manager Control utility (GDSCTL).

3. Set the ORACLE_HOME environment variable to the directory you specified during installation.
4. Add the $ORACLE_HOME/bin directory created for the global service manager to the PATH environment variable.
5. Set the TNS_ADMIN environment variable set to $ORACLE_HOME/network/admin.

The following are the basic steps you would take to implement Global Data Services.

1. Install Oracle GDS global service manager software on global service manager servers.
   • Minimum of 1 global service manager for each region
   • Recommended 3 global service managers for each region
2. Pre-create the Oracle GDS catalog database.
3. Set up Oracle GDS Administrator accounts and privileges.
4. Configure Oracle GDS.
   • Create the GDS catalog and standby databases.
   • Add global service managers, regions, pools, databases, and global services.
5. Set up client connectivity.

The following steps describe how to implement Global Data Services.

This example configuration of Global Data Services (GDS) uses an Administrator-managed Oracle RAC database. Administrator-managed deployment means that you configure database services to run on specific instances belonging to a particular database using a preferred and available designation.

Policy-managed deployment is based on server pools, where database services run within a server pool as singletons or uniformly across all of the servers in the server pool. Databases are deployed in one or more server pools, and the size of the server pools determines the number of database instances in the deployment.

1. Create and prepare a GDS catalog database.

   GDS uses a catalog database to store meta-data relating to the layout and status of the GDS configuration. For maximum availability, Oracle recommends that the GDS catalog database be deployed independently and that Oracle's high-availability features, such as Oracle Real Application Clusters (Oracle RAC) and Oracle Data Guard, be used to protect the catalog database against outages.

2. Create the GSM_ADMIN user and assign that user the GSMADMIN_ROLE.

   Note that by default, the password for both GSM_ADMIN, GSMUSER, and GSMCATUSER expires after 180 days.

   SQL> create user gsm_admin identified by password;
   
   User created.
   
   SQL> grant gsmadmin_role to gsm_admin;
   
   Grant succeeded.
   
   SQL> exit

3. With the environment configured for the global service manager home, use GDSCTL to create the GDS catalog database with Auto VNCR disabled (Auto VNCR can cause problems with Oracle RAC deployments).

   GDSCTL> create gdscatalog -database gdscat -user gsm_admin -autovncr OFF

4. Connect to the catalog database, unlock the GSMCATUSER user, and set the password.

   SQL> alter user gsmcatuser account unlock;
   
   User altered.
   
   SQL> alter user gsmcatuser identified by password;
   
   User altered.

5. With the environment configured for the global service manager home, use GDSCTL to connect to, create, and start the global service manager listeners.
   As a best practice, global service manager listeners should reside on hardware separate from that hosting the Oracle Databases in the GDS configuration. The resource requirements for hardware needed to run global service manager listeners are lightweight and can easily be accommodated using virtual machines.

   GDSCTL> add gsm -gsm gsm1 -listener 1522 -catalog gdscat
   
   "gsmcatuser" password:
   
   Create credential oracle.security.client.connect_string1
   
   GSM successfully added
   
   GDSCTL>start gsm -gsm gsm1
   
   GSM is started successfully
   
   GDSCTL>status
   
   Alias GSM1
   Version 19.17.0.3.0
   Start Date 13-APR-2023 09:40:59
   Trace Level off
   Listener Log File
    /u01/app/oracle/diag/gsm/hostname/gsm1/alert/log.xml
   Listener Trace File
    /u01/app/oracle/diag/gsm/hostname/gsm1/trace/ora_64863_139739749930432.trc
   Endpoint summary
   (ADDRESS=(HOST=hostname.example.com)(PORT=1522)(PROTOCOL=tcp))
   GSMOCI Version 0.6.11
   Mastership Y
   Connected to GDS catalog Y
   Process Id 64883
   Number of reconnections 0
   Pending tasks. Total 0
   Tasks in process. Total 0
   Regional Mastership TRUE
   Total messages published 0
   Time Zone -04:00
   Orphaned Buddy Regions: None
   GDS region regionora

6. With the environment configured for the global service manager home, use GDSCTL to create a default GDS pool and default region.

   GDSCTL> add gdspool -gdspool sales
   
   GDSCTL> add region -region slc
   
   GDSCTL> add region -region sca

7. With Auto VNCR disabled during GDS catalog creation to avoid issues, use GDSCTL to add hosts using the add invitednode command, using the host name or IP address appropriately.

   GDSCTL> add invitednode 192.0.2.1
   
   GDSCTL> add invitednode host1.example.com

8. Unlock the GSMUSER account.
   Before adding a database to a pool, the database administrator should unlock the GSMUSER account and give the password to the GDS pool administrator, as shown in the following example.

   SQL> alter user gsmuser account unlock;
   
   User altered.
   
   SQL> alter user gsmuser identified by password;
   
   User altered.

9. Add databases to the GDS pool.

   To be part of a GDS pool, a database must use a server parameter file (SPFILE). An Oracle RAC database should also have SCAN set up.

   To add a database, connect to the GDS catalog using the GDS pool or GDS administrator credentials. For example, without Data Guard, the following add database command can be used.

   Note:

   When using Oracle Active Data Guard with GDS, use add brokerconfig instead of add database , and then use modify database to configure the standby database (see add brokerconfig). The syntax for these commands would be like the following:

   GDSCTL> add brokerconfig -connect <primary_db> -gdspool <dbpool> -region <dc> -pwd <gsmuser_pwd>
   
   GDSCTL> modify database -database <standby_db> -connect <dc> -gdspool <dbpool> -region <dc> -pwd <gsmuser_pwd>

   Database instance registration with a global service manager succeeds only when the request originates from a valid node. If a host on which a database resides contains multiple network interfaces, the auto-configuration could register the wrong set of IP addresses, leading to the database registration being rejected.

10. Correct any rejected registration and properly discover all database instances.

    If a firewall exists between the global service managers, and the databases and the ports are not opened, the registration fails. From the global service manageralert log, you will see entries similar to the following.

    Listener(VNCR option 1) rejected Registration request from destination
    
    192.0.2.2
    
    Listener(VNCR option 1) rejected Registration request from destination
    
    192.0.2.3

    You will find that the database object exists in the GDS catalog, but some or all instances associated with specific hosts are missing.

    GDSCTL> databases
    
    Database: "mts" Registered: Y State: Ok ONS: Y. Role: PRIMARY
    
    Instances: 1 Region: slc
    
    Registered instances:
    
    sales%1

    To correct the rejected registration and properly discover all database instances, run add invitednode using the rejected IP address listed in the global service manager alert log.

11. If there is a firewall between the global service managers and the database, then once the ports have been opened and verified using tnsping, issue the add invitenode command as shown here.

    GDSCTL> add invitednode 192.0.2.3
    
    GDSCTL>databases
    
    Database: "mts" Registered: Y State: Ok ONS: Y. Role: PRIMARY
    
    Instances: 2 Region: slc
    
    Registered instances:
    
    sales%1
    
    sales%2

12. Create a service on the GDS pool databases.

    The GDSCTL add service command creates a service on the GDS pool databases.

    GDSCTL> add service -service sales_sb -preferred_all -gdspool sales -notification TRUE

    If this is an Oracle RAC database being added with multiple instances, then you must modify the service to add the database instances.

    GDSCTL> modify service -gdspool sales -service sales_sb -database mts -add_instances -preferred mts1,mts2
    
    GDSCTL> modify service -gdspool sales -service sales_sb -database stm -add_instances -preferred stm1,stm2
    
    GDSCTL> start service -service sales_sb -gdspool sales

13. Verify that the global service is running.

    GDSCTL> services
    
    Service "sales_sb.sales.oradbcloud" has 2 instance(s). Affinity: ANYWHERE
    
    Instance "sales%1", name: "mts1", db: "mts", region: "slc", status: ready.
    
    Instance "sales%2", name: "mts2", db: "mts", region: "slc", status: ready.

Oracle MAA recommends the following best practices for implementing Global Data Services:

• Each client communicates using an Oracle-integrated connection pool such as UCP, OCI, or ODP.NET. The connection pools will be notified about any service failovers and load balancing advisory notifications using Fast Application Notification Events.

• Run three global service managers in each region. Create three global service managers in each region so that if one global service manager goes down, you have two remaining global service managers to provide redundancy. Each global service manager should reside on separate hardware. Global service managers enable connection routing among replicated databases. A global service manager is a stateless, lightweight, and intelligent listener that can repopulate its metadata from the GDS catalog.

• Protect the GDS catalog database with Oracle Data Guard.The GDS catalog is a small (less than 100 GB) repository that hosts the metadata of the GDS configuration, regions, global service managers, global services, databases, and so on. MAA recommends that you set up a local Data Guard standby database configured with Maximum Availability database protection mode, Data Guard Fast-Start failover, and a remote physical standby database. All GDS catalog standby databases should use Oracle Active Data Guard for the best data protection and reside on separate hardware and storage.