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Lesson 5 Starting Oracle Shared Server
Objective Start Shared Server and connect to a database.

Starting Shared Server before using SQL *Plus

A DBA needs to start Oracle Shared Server before beginning to use SQL*Plus. SQL*Plus is a client application that connects to the Oracle database server to perform SQL operations. In order to connect to the database server, SQL*Plus needs the database server to be running. Oracle Shared Server is a type of database server architecture that uses a pool of shared server processes to handle client requests. When a client application connects to the database, it is assigned to a shared server process. The shared server process then executes the SQL statements issued by the client application.
To start Oracle Shared Server, a DBA can use the following command:
$ORACLE_HOME/bin/oracle -shared_servers

This will start the database in shared server mode with the default number of shared server processes. The DBA can also specify a custom number of shared server processes using the `-shared_servers` parameter. Once Oracle Shared Server is running, a DBA can connect to the database using SQL*Plus or another client application.
$ sqlplus /nolog
Enter password: tiger

Connected to:
Oracle Database 19c Enterprise Edition Release - Production
Version - 64bit Production


If Oracle Shared Server is not running, a DBA will not be able to connect to the database using SQL*Plus or another client application.

Creation of Internal Password in Oracle 13c

During the installation of Oracle 13c, the installer does "not directly create an internal password". However, it does configure several internal users and sets passwords for some of them. Here's a breakdown:
Internal Users and Passwords:
  • SYSMAN: This user has administrative privileges and is used for various internal tasks during database startup and management. "No password is set by default", and you must define it during the installation process.
  • SYS: This is the root user with full privileges but is typically disabled for security reasons. "No password is set by default".
  • SYSTEM: This user has limited privileges for administrative tasks. "A password is automatically generated by the installer".
  • MGMT_VIEW: This user provides access to management views. "No password is set by default" and auto-generation can be enabled during installation.

Important points to remember:
  • SYSMAN password is crucial: Ensure you set a strong and secure password for the SYSMAN user during installation.
  • Other passwords: While passwords for SYSTEM and MGMT_VIEW are set, it's recommended to change them to enhance security after installation.
  • Secure internal users: Remember to follow best practices for managing internal users, such as using strong passwords, limiting privileges, and monitoring access.

Additional notes:
  • The term "internal password" might sometimes refer to the SYSMAN password in specific contexts.
  • The option to set passwords for SYSMAN and MGMT_VIEW during installation might vary slightly depending on the specific installation options and platform you choose.

Historial Noted regarding Server Manager prior to Oracle 9i

  1. Know the executable name: You should now know the name for your Server Manager executable, so let us start it. If you are not running Oracle software, just make sure you know the executable name for the version that you will eventually be running. If you are running Oracle, go ahead and issue the command. If you are on Windows, you will need to open a command prompt window first. The following example was done under NT using Oracle release 8.0.4: The following commands have been deprecated since Oracle Server Manager has been retired since Oracle 9i.
    Note: The following information is for only for historical reference.
    Oracle Server Manager Release - Production
    (c) Copyright 1998, Oracle Corporation.
    All Rights Reserved.
    Oracle8 Release - Production
    PL/SQL Release - Production
  2. Connecting to a Database using Server Manager: After you start Server Manager, the next step is to connect to a database. You can do this by using the CONNECT command. The following example shows one way to connect to your default database. The internal keyword tells Server Manager that you want to connect as an administrative user.
  3. Connecting as Administrative User: There are two basic ways to connect to an Oracle database:
    • as an administrative user and
    • as a normal user.
  4. Connect as DBA or User: For 90% of the tasks that you do, you will find that you can connect either way and it will not matter. Any priviledged user can connect normally to the database and still be able to
    • run queries,
    • create and alter schema objects.

    However, to start up or shut down a database, recover a database, or create a new database, you must be connected as an administrator.
    The keyword internal represents one way to tell Server Manager that you want to connect as an administrator. Two other keywords may also be used. These are
    • SYSDBA and
    • SYSOPER.
    In order to use SYSDBA and SYSOPER, you must configure a database password file. We will do that in, Managing Users and Connectivity, the next course in this series.
  5. Password Creation: Depending on choices that you made when you installed Oracle, you might be prompted for a password. This is a special password known as the internal password. The default for that password is “oracle,” but if you chose a different internal password when you installed Oracle, use that. If someone else created this database, and you do not know the internal password, then you should ask the person who created the database to help you connect to it. Go ahead and try connecting to your default database. There exists a GUI version of Server Manager, but we will not address the GUI version in this course.
  6. Legacy GUI Version of Oracle Server Manager: For UNIX users, Oracle supplies a GUI version of Server Manager. The command to start it is: svrmgrm. The “m” at the end of the command stands for “Motif”. Motif is an X-Windows-based windowing manager that you need in order to use the GUI version. To start the GUI version of Server Manager from an X-windows client, you first open a Telnet session, then issue the svrmgrm command. Enterprise Manager is Oracle's flagship database administration tool, and it's GUI-based. If you want to learn a GUI administration tool, you are much better off focusing your efforts on learning Enterprise Manager.
  7. GUI Tool to manage Oracle Databases: In 1996, Oracle made a first attempt at releasing a GUI tool to manage its databases. This was Oracle Server Manager, which featured a 1) command line and 2) GUI interface. In the past, most DBAs resorted to using only the command line interface of Server Manager, called Server Manager/Line Mode. This was because at that time it was easier to get things done using the command line interface. In addition, the first few releases of the GUI interface had limited administrative capabilities. Oracle then released a new version, Oracle Enterprise Manager. OEM 9.2 was released in 2002, which was when larger numbers of DBAs first started using Enterprise Manager. The console product was Java-based and had to be installed as a separate product on each workstation accessing the central repository of Enterprise Manager. This OEM 9.2 was a stand-alone console mode without a repository and a mode that connected to a central repository. Many DBAs used the stand-alone mode without the repository. As a result, there was no central repository of database information in many sites even though OEM 9.2 was being used.
  8. In 2004, Oracle rewrote the product with a new architecture based on its application server technology Oracle 9i. The console was now browser-based and could be accessed from any workstation on the corporate network without the need to install software on any workstation. The only installation required was the 1) repository and 2) server agents. The stand-alone mode was no longer possible, thus forcing the use of a centralized repository. The Enterprise Manager product that allowed management of multiple databases and servers was named Grid Control, after use of the 'g' letter in the Oracle 10g database. The emphasis it laid on the Grid in the year 2006 was for the future of computing. DBAs can understand how Grid Control can assist in the daily database administration activities. In addition, the DBA can make the automation of jobs without scripts, removing much of the dependence on UNIX shell scripts and cron jobs.

Note: On Unix systems, you must be a member of the DBA group to connect as internal.
SQL> connect internal


Grid Control

Grid Control can also be used by System Administrators for most of them would appreciate its
  1. host performance monitoring capabilities,
  2. performance history of host CPU,
  3. memory utilization being stored in the repository, and
  4. the host configuration comparison capabilities for troubleshooting.
Question: How can Grid Control help IT managers
  1. achieve an overall view of the corporate infrastructure system and
  2. provide reports and information on security compliance,
  3. application level performance dashboards,
  4. database versions in use,
  5. licensing usage,
  6. conformation to standards,
  7. unnecessary storage allocation, and
  8. unused databases?
Answer: The OEM Grid Control can create databases in a matter of minutes .

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