oracle ocp studying

Chapter 4 : Naming Method Configuration

Chapter 5 : Usage and Configuration of the Oracle Shared Server

Chapter 6 : Backup and Recovery Overview

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Chapter 4 : Naming Method Configuration

Naming methods are used by a client application to resolve a connect identifier to a connect descriptor when attempting to connect to a database service.

Oracle Net provides five naming methods:

Small Organizations :

1 , Host naming : Enables Users in a TCP/IP environment to resolve names through their existing name resolution service

1.1 connect to an Oracle database service using Oracle Net Services Client Software

1.2 client and server are connecting using TCP/IP protocol

1.3 host names are resolved through an IP address translation mechanism such as DNS ,NIS or a local /etc/hosts file( DNS:Domain Name Services , NIS:Network Information Services)

1.4 No advanced features such as Oracle Connection Manager or security options are used

Advantages of Host Naming Method :

-- Requires minimal user configuration.

-- Eliminates the need to create and maintain a local names configuraton file(tnsnames.ora)

-- Eliminates the need to understand Oracle Names or Oracle Internet Directory administration procedures

Example :

sqlnet.ora

------- names.directory_path = (HOSTNAME)

2 , Local naming : Locates network addresses by using information configured and stored on each individual client's tnsnames.ora file.

Advantages of Local Naming :

-- Provides a relatively straightforward method for resolving service name addresses.

-- Resolves service names across networks running different protocols.

-- Can easily be configured by using a graphical configuration tool.

Configuring Tools :

-- Oracle Net Manager

The Sqlnet.ora File:

-- the sqlnet.ora file controls the behavior of Oracle Net Services.The default location is %ORACLE_HOME%--network--admin on windows. The default location can be overridden by defining the TNS_ADMIN enviroment variable.

Notes :

---- Test that the service is reachable using tnsping

--- Verify that you are connected to the correct instance by querying the V$INSTANCE view

Large Organizations :

3 , Directory naming : Resolves a database service or net service name to a connect descriptor,stored in a central directory server.

4 , Oracle Names : Oracle directory service made up of a system of Oracle Names servers that provide name-to-address resolution for each service on the network.

5 , External naming : Uses a supported third-party naming service

Chapter 5 : Usage and Configuration of the Oracle Shared Server

The Oracle Shared Server architecture requires Oracle Net Services. Even if the user processes exist on the same machine as the oracle instance.

Server Configurations:

* Dedicated server process (1: 1 user processes)

--- Features of dedicated server process configuration:

------- 1, The user proces and server process are separate.

------- 2, Each user prcess has its own server process.

------- 3, The user and server processes can run on different machines to take advantage of distributed processing.

------- 4, There is a one-to-one ratio between the user and server processes.

------- 5, Even when the user process is not making a database request,the dedicated server exists but remains idle.

* Shared server process (1:n user processes)

Under the Oracle Shared Server architecture ,client-user processes ultimately connect to a dispatcher.The PMON process registers the location and load of the dispatchers with the listener,enabling the listener to forward requests to the least utilized dispatcher.Service registration does not require configuration in the listener.ora file.

Benefits of Oracle Shared Server

** Reduces memory usage and system overhead

** Reduces the number of processes against an instance

** Reduces the number of idle server processes

** Increases the number of possible users

** Archieve load balancing

Using a Dedicated Server with Oracle Shared Server

--- You must use a dedicated server process when:

------- Submitting batch jobs(it is expected that there will be little or no idle time)

------- Connecting as sysdba to startup ,shutdown ,or perform recovery

For Example(Tnsnames.ora):

Test=

------(DESCRIPTION=

-----------(ADDRESS=

-----------------(PROTOCOL=TCP)

-----------------(HOST=COMPUTER-YSJ.VICKA.COM)

-----------------(PORT=1521)

-----------)

-----------(CONNECT_DATA= (SERVICE_NAME=ORCVK.VICKA.COM)-----------------(SERVER=DEDICATED)

-----------)

)

Configuring Oracle Shared Server

Parameters------------Required----Dynamic---Default

dispatchers------------------------Y--------------Y--------------NULL

shared_servers--------------------Y--------------Y--------------0

max_dispatchers------------------N--------------N--------------5

max_shared_servers--------------N--------------N--------20 or 2*shared_servers

circuits----------------------------N-------------N--------sessions or 0

shared_server_sessions-----------N-------------N--------lesser of circuits and seessions-5

large_pool_size

sessions