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CICS Resource Definitions (RDO): Resource Definition Online

Resource Definition Online (RDO) is CICS's comprehensive system for defining, managing, and administering all CICS resources. This powerful tool provides an interactive interface for creating and modifying resource definitions without requiring system restarts, making CICS administration more efficient and flexible than ever before.

System Administration
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What is Resource Definition Online (RDO)?

Resource Definition Online (RDO) is CICS's modern approach to resource management, providing an interactive, online system for defining and managing all CICS resources. Unlike traditional methods that required system restarts and static configuration files, RDO allows administrators to dynamically create, modify, and delete resource definitions while the system is running.

Key Features of RDO

Interactive Interface: Command-line interface for resource management
Dynamic Updates: Changes take effect immediately without restarts
Validation: Built-in validation to prevent configuration errors
Organization: Groups and lists for logical resource organization
Flexibility: Support for all CICS resource types
Security: Integration with RACF for access control

The DFHCSD Dataset

At the heart of RDO is the DFHCSD (CICS System Definition) dataset, which serves as the central repository for all CICS resource definitions.

DFHCSD Dataset Characteristics

VSAM Format: Stored as a VSAM Key Sequenced Data Set (KSDS)
Central Repository: Contains all CICS resource definitions
Persistent Storage: Definitions survive system restarts
Backup Capability: Can be backed up and restored
Version Control: Supports multiple versions of definitions
Access Control: Protected by RACF security

DFHCSD Dataset Structure

System Definitions: Global system parameters
Group Definitions: Logical groupings of resources
Resource Definitions: Individual resource specifications
List Definitions: Collections of related resources
Security Definitions: Access control specifications

RDO Commands Overview

RDO provides three primary commands for resource management, each serving a specific purpose in the resource definition process.

A

CEDA - Define Command

The CEDA command is used to create new resource definitions:

Purpose:Create new resource definitions
Syntax:CEDA DEFINE resource-type resource-name
Validation:Performs syntax and semantic validation
Installation:Can install definitions immediately
Groups:Can assign resources to groups

Example CEDA Commands:

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CEDA DEFINE PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP)
 CEDA DEFINE TRANSACTION(PAY1) PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP)
 CEDA DEFINE FILE(CUSTOMER) DSNAME(CUST.FILE) GROUP(PAYROLL_GROUP)
Line 1: Defines PAYROLL program and assigns it to PAYROLL_GROUP
Line 2: Defines PAY1 transaction linked to PAYROLL program in PAYROLL_GROUP
Line 3: Defines CUSTOMER file pointing to CUST.FILE dataset in PAYROLL_GROUP
B

CEDB - Browse Command

The CEDB command allows browsing and viewing existing resource definitions:

Purpose:View existing resource definitions
Syntax:CEDB BROWSE resource-type resource-name
Display:Shows all attributes of the resource
Search:Can search for specific resources
List:Can list all resources of a type

Example CEDB Commands:

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CEDB BROWSE PROGRAM(PAYROLL)
 CEDB BROWSE TRANSACTION(PAY1)
 CEDB BROWSE GROUP(PAYROLL_GROUP)
Line 1: Displays all attributes and settings of the PAYROLL program
Line 2: Shows configuration details for the PAY1 transaction
Line 3: Lists all resources contained within PAYROLL_GROUP
C

CEDC - Change Command

The CEDC command is used to modify existing resource definitions:

Purpose:Modify existing resource definitions
Syntax:CEDC CHANGE resource-type resource-name
Validation:Validates changes before applying
Installation:Can install changes immediately
Backup:Creates backup of original definition

Example CEDC Commands:

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CEDC CHANGE PROGRAM(PAYROLL) NEWCOPY(YES)
 CEDC CHANGE TRANSACTION(PAY1) PRIORITY(5)
 CEDC CHANGE FILE(CUSTOMER) DISPOSITION(SHR)
Line 1: Modifies PAYROLL program to force reload when updated
Line 2: Changes PAY1 transaction priority to level 5 for scheduling
Line 3: Updates CUSTOMER file to allow shared access by multiple users

Groups and Lists in RDO

Groups and lists are organizational structures that help manage CICS resources efficiently and logically.

Groups

Groups provide a way to organize related resources together:

Logical Organization: Groups related resources together
Installation Unit: Can install entire groups at once
Security Control: Can apply security at group level
Management: Simplifies resource administration
Dependencies: Can manage resource dependencies

Example Group Definition:

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CEDA DEFINE GROUP(PAYROLL_GROUP) DESCR('Payroll Application Resources')
 CEDA DEFINE PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP)
 CEDA DEFINE TRANSACTION(PAY1) PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP)
Line 1: Creates PAYROLL_GROUP with descriptive text for organization
Line 2: Adds PAYROLL program to the PAYROLL_GROUP for logical grouping
Line 3: Links PAY1 transaction to PAYROLL program within PAYROLL_GROUP

Lists

Lists are collections of resources that can be referenced together:

Resource Collections: Groups related resources
Reference Mechanism: Can reference multiple resources
Access Control: Can control access to resource collections
Efficiency: Reduces repetitive definitions
Maintenance: Simplifies resource maintenance

Types of Lists:

Program Lists
Transaction Lists
File Lists
Terminal Lists

Resource Types in RDO

RDO supports a comprehensive range of CICS resource types, each with specific attributes and parameters.

Program Resources

Program resources define application programs that can be executed by CICS:

  • Purpose: Define executable programs
  • Key Attributes: Program name, load library, language
  • Security: Access control and authorization
  • Performance: Memory management and optimization
  • Compatibility: Language and environment support

Example Program Definition:

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CEDA DEFINE PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP)
CEDA DEFINE PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP) LANGUAGE(COBOL)
CEDA DEFINE PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP) LANGUAGE(COBOL) NEWCOPY(YES)
CEDA DEFINE PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP) LANGUAGE(COBOL) NEWCOPY(YES) RELOAD(YES)
Line 1: Basic program definition - defines PAYROLL program in PAYROLL_GROUP
Line 2: Adds LANGUAGE(COBOL) - specifies the program is written in COBOL
Line 3: Adds NEWCOPY(YES) - forces program reload when modified
Line 4: Adds RELOAD(YES) - allows program to be reloaded while active

Transaction Resources

Transaction resources define the transactions that users can invoke:

  • Purpose: Define user-invokable transactions
  • Key Attributes: Transaction ID, program, priority
  • Security: User access control
  • Performance: Priority and scheduling
  • Monitoring: Transaction tracking and statistics

Example Transaction Definition:

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CEDA DEFINE TRANSACTION(PAY1) PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP)
CEDA DEFINE TRANSACTION(PAY1) PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP) PRIORITY(5)
CEDA DEFINE TRANSACTION(PAY1) PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP) PRIORITY(5) SECURITY(YES)
Line 1: Basic transaction definition - defines PAY1 transaction linked to PAYROLL program
Line 2: Adds PRIORITY(5) - sets transaction priority level for scheduling
Line 3: Adds SECURITY(YES) - enables RACF security checking for this transaction

File Resources

File resources define data files that CICS applications can access:

  • Purpose: Define data file access
  • Key Attributes: File name, dataset name, organization
  • Access Control: Read/write permissions
  • Performance: Buffer management and optimization
  • Recovery: File recovery and backup

Example File Definition:

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CEDA DEFINE FILE(EMPLOYEE) DSNAME(EMP.FILE) GROUP(PAYROLL_GROUP)
CEDA DEFINE FILE(EMPLOYEE) DSNAME(EMP.FILE) GROUP(PAYROLL_GROUP) DISPOSITION(SHR)
CEDA DEFINE FILE(EMPLOYEE) DSNAME(EMP.FILE) GROUP(PAYROLL_GROUP) DISPOSITION(SHR) RECORDFORMAT(F)
Line 1: Basic file definition - defines EMPLOYEE file pointing to EMP.FILE dataset
Line 2: Adds DISPOSITION(SHR) - allows shared access to the file
Line 3: Adds RECORDFORMAT(F) - specifies fixed-length record format

Terminal Resources

Terminal resources define the terminals that can connect to CICS:

  • Purpose: Define terminal connections
  • Key Attributes: Terminal ID, type, model
  • Communication: Network and protocol settings
  • Security: Terminal access control
  • Features: Terminal capabilities and options

Resource Installation and Activation

Once resources are defined, they must be installed to become active in the CICS system.

Installation Process

The installation process involves several steps:

  1. 1Validation: CICS validates the resource definition
  2. 2Dependency Check: Verifies dependent resources exist
  3. 3Storage Allocation: Allocates necessary storage
  4. 4Table Update: Updates internal CICS tables
  5. 5Activation: Makes the resource available for use

Installation Commands

Individual Resource Installation:

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CEDA INSTALL PROGRAM(PAYROLL)
CEDA INSTALL TRANSACTION(PAY1)
CEDA INSTALL FILE(EMPLOYEE)
Line 1: Installs PAYROLL program into active CICS system
Line 2: Activates PAY1 transaction for user access
Line 3: Makes EMPLOYEE file available for application use

Group Installation:

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CEDA INSTALL GROUP(PAYROLL_GROUP)
Line 1: Installs all resources in PAYROLL_GROUP simultaneously

Resource Validation and Error Handling

RDO provides comprehensive validation to ensure resource definitions are correct and consistent.

Validation Types

RDO performs several types of validation:

  • Syntax Validation: Checks command syntax and format
  • Semantic Validation: Validates parameter values and relationships
  • Dependency Validation: Ensures referenced resources exist
  • Security Validation: Verifies security settings
  • Performance Validation: Checks performance-related parameters

Common Validation Errors

Common validation errors include:

  • Missing Dependencies: Referenced resources don't exist
  • Invalid Parameters: Parameter values are out of range
  • Security Violations: Insufficient security permissions
  • Syntax Errors: Incorrect command syntax
  • Resource Conflicts: Duplicate resource names

RDO Security and Access Control

RDO integrates with RACF to provide comprehensive security for resource definitions.

Security Features

RDO security features include:

  • User Authentication: Verifies user identity
  • Authorization: Controls access to resource definitions
  • Audit Logging: Records all RDO activities
  • Resource Protection: Protects sensitive resources
  • Group Security: Security at group level

Security Commands

Security-related RDO commands:

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CEDA DEFINE PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP) SECURITY(YES)
CEDA DEFINE TRANSACTION(PAY1) PROGRAM(PAYROLL) GROUP(PAYROLL_GROUP) SECURITY(YES)
CEDA DEFINE FILE(EMPLOYEE) DSNAME(EMP.FILE) GROUP(PAYROLL_GROUP) SECURITY(YES)
Line 1: Enables RACF security checking for PAYROLL program access
Line 2: Requires user authorization to execute PAY1 transaction
Line 3: Protects EMPLOYEE file with RACF access control

RDO Best Practices

Following best practices ensures efficient and reliable resource management.

Organization Best Practices

Group Organization:

  • Use logical group names that reflect application or function
  • Group related resources together
  • Use consistent naming conventions
  • Document group purposes and contents
  • Plan for future expansion

Security Best Practices

Security Guidelines:

  • Enable security for all production resources
  • Use RACF profiles for access control
  • Regularly review security settings
  • Monitor access attempts and violations
  • Implement least privilege principles

Performance Best Practices

Performance Guidelines:

  • Use appropriate resource attributes for performance
  • Monitor resource usage and performance
  • Optimize resource definitions for workload
  • Use groups for efficient installation
  • Plan for capacity and scalability

RDO vs. Traditional Methods

RDO represents a significant improvement over traditional CICS resource definition methods.

Advantages of RDO

RDO Advantages:

  • Dynamic Updates: Changes take effect immediately
  • No Restarts: System restarts not required
  • Better Organization: Groups and lists for organization
  • Enhanced Validation: Comprehensive error checking
  • Improved Security: Better security integration
  • Easier Administration: Simplified management interface

Traditional Method Limitations

Traditional Method Disadvantages:

  • Static Configuration: Changes require system restarts
  • Limited Organization: No logical grouping
  • Manual Validation: Error-prone manual checking
  • Security Challenges: Limited security integration
  • Administrative Overhead: More complex management

Exercises and Practice

Exercise 1: Resource Definition Creation

Create a complete set of RDO definitions for a simple banking application. Include programs, transactions, files, and terminals. Organize them into logical groups and implement appropriate security settings.

Exercise 2: Resource Management Scenario

Design a scenario where you need to modify an existing application. Show the RDO commands needed to add new programs, update existing transactions, and install the changes without affecting running applications.

Exercise 3: Security Implementation

Plan and implement a security strategy for a CICS application using RDO. Define the necessary RACF profiles, implement resource-level security, and create audit procedures for monitoring access.

Quiz: Test Your Knowledge

Quick Quiz

1. What does RDO stand for in CICS?

Answer: Resource Definition Online

2. What is the DFHCSD dataset used for?

Answer: Storing all CICS resource definitions

3. What are the three main RDO commands?

Answer: CEDA (Define), CEDB (Browse), CEDC (Change)

4. What is the purpose of groups in RDO?

Answer: To organize related resources together and simplify management

5. How do you activate resource definitions in RDO?

Answer: Using the CEDA INSTALL command

Summary

Resource Definition Online (RDO) is a powerful and flexible system for managing CICS resources. It provides an interactive, online interface for creating, modifying, and deleting resource definitions without requiring system restarts, making CICS administration more efficient and user-friendly.

The DFHCSD dataset serves as the central repository for all resource definitions, while the CEDA, CEDB, and CEDC commands provide the interface for resource management. Groups and lists offer organizational capabilities that simplify resource administration and improve maintainability.

RDO's comprehensive validation, security integration, and dynamic update capabilities make it the preferred method for CICS resource management. By following best practices and understanding the system's capabilities, administrators can efficiently manage complex CICS environments while maintaining security and performance.

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