Oracle Internet Directory
Oracle Application Server Tips by Burleson
The Oracle Internet Directory (OID) is a
Lightweight Directory Access Protocol (LDAP) directory service that
provides centralized storage of information about users,
applications, and resources in your enterprise. Coupled with SSO,
OID allows end-users to sign-on one time and use their pre-defined
OID credential (set-up by the DBA). This credential defines
those components of Oracle9iAS with which the end-user is allowed to
Because it is LDAP-compliant, OID can be
viewed as a simple lookup mechanism for web services. For
example, LDAP entries can be used instead of entries in the
traditional tnsnames.ora file, thereby allowing connectivity for
clients anywhere on your network. This techniques has replaced
the obsolete Oracle*Names tool as a method for defining services for
In sum, OID is an easy-to-configure tool for
defining end-user access with Oracle9iAS. Because OID is
tightly-coupled with SSO and Oracle advanced security, OID is a
critical component is Oracle security management.
Management of OID is made quite simple with
a GUI dubbed Oracle Directory Manager (ODM). While we will be
discussing ODM in great detail in Chapter 12, Oracle9iAS Security,
for now you should know that ODM is a tool for the Oracle9iAS
administrator to manage data access rules.
Metadata Repository (infrastructure)
The metadata repository is a critical
component of Oracle9iAS because it allows for a common management
interface between multiple instances of Oracle9iAS and the other
components. The metadata repository is commonly referred to as
the infrastructure, and this is a critical common component to all
Oracle9iAS farms and all Oracle9iAS components that share a common
definition. We will discuss the infrastructure in great detail
in Chapter 3, Oracle9iAS Infrastructure.
Oracle Management Server (OMS)
The OMS allows the administrator to include
the Application Server in centrally managed configuration using
Oracle Enterprise Manager (a separate product). OMS is a
component of the Oracle Enterprise Manager (OEM) Console, and the
OMS processes enable the management of the Oracle9iAS instances,
databases, and other Oracle9iAS components. The foremost feature of
OMS is its ability to store OEM data inside the metadata repository
infrastructure. This storage ability of OMS allows Oracle9iAS
administrators to share server configuration information, scheduled
Oracle9iAS events and jobs, and share notifications for Oracle9iAS
failures. To start OMS you use the emctl command and issue
emctl start oms command to start the webservers and OMS processes.
Because OMS is the ?glue? that ties all of
the Oracle9iAS components together, we will be visiting OMS
functionality throughout this text. OMS provides the important
functions of user administration and manages the flow of information
between the OEM console and all managed nodes. OEM allows for
any server to become a managed node by installing an Oracle
intelligent agent (OIA), thereby making it accessible with the
central administrative GUI. An OIA is a daemon process that
serves to interface with the database and operating system on each
server within each Oracle9iAS farm. The intelligent agent
performs localized execution of tasks as directed by the OMS, and
for Oracle servers, the OIA performs time-based database monitoring.
The concept of managed nodes allows ODM to become very powerful,
allowing the Oracle9iAS DBA to quickly apply configuration changes
to many server components.
Oracle9iAS TopLink is an important component
for Java developers because it provides a mechanism for making Java
objects persistent across sessions. In object-oriented
languages such as Java, C# or C++, objects can be instantiated and
destroyed according to the needs of the program.
The problem is that OO languages like Java
create objects in the RAM heap, and upon termination of the program,
all of the programs objects are destroyed. Oracle9iAS TopLink
is a persistence framework that enables object persistence by
supplying routines that can be invoked to store Java objects in
relational database tables (in any relational database that supports
JDBC). In addition, Oracle9iAS TopLink provides a GUI tool,
the Mapping Workbench, that greatly simplifies the task of mapping
Java objects and their attributes to database tables. TopLink
also provides powerful features like a query framework, object-level
transaction support, relationship mappings, object caching, and much
more. Prior to TopLink, the programmer would have to write
custom JDBC code to store and retrieve the Java object?s attributes
to/from a relational table. This is extremely time-consuming and
error prone plus difficult to change. TopLink is built on top of
JDBC but does not require developers to use JDBC (or even SQL!).
Oracle9iAS TopLink supports all J2EE compliant application servers,
and can be used to store object data from standard Java objects, as
well as entity beans. Please refer to the Oracle9iAS TopLink
documentation for more information.
Next, let?s introduce the main topic of this
text, the administration and management of Oracle9iAS.
This is an excerpt from "Oracle
10g Application Server Administration Handbook" by Don Burleson
and John Garmany.