Inconsistent - Not matching

Enhanced Definition

In the context of mainframe systems, "inconsistent" refers to a state where data, system configurations, or application states do not align with expected values, predefined rules, or a synchronized condition. This mismatch can lead to data integrity issues, erroneous processing, or system instability, indicating a deviation from a valid and reliable state.

Key Characteristics

- Data Mismatch: Occurs when multiple copies of the same data, or related data elements across different systems or tables, do not hold identical or logically synchronized values.
- Configuration Drift: Refers to discrepancies between the actual configuration of a system component (e.g., PARMLIB members, security rules) and its intended or documented baseline.
- State Violation: A system or application enters a state that violates its defined operational rules or integrity constraints, often due to incomplete transactions or concurrent updates.
- Impact on Reliability: Inconsistency can lead to unpredictable application behavior, incorrect reporting, data corruption, or even system outages if critical control blocks or datasets are affected.
- Detection Challenges: Identifying inconsistencies often requires sophisticated monitoring, data validation routines, and comparison tools, as they may not always manifest as immediate errors.

Use Cases

- Database Integrity: A DB2 or IMS transaction fails mid-update, leaving some related records updated while others are not, resulting in an inconsistent view of the data across related tables or segments.
- Distributed Data Synchronization: Data replicated between a primary z/OS system and a disaster recovery site becomes inconsistent due to network issues or replication failures, impacting recovery point objectives.
- Application Logic Errors: A COBOL program processes a file, but due to a bug, updates a control field incorrectly, making it inconsistent with the actual number of records processed in the file.
- System Configuration: A SYSMOD installation or a manual update to a PARMLIB member is incomplete or incorrect, leading to an inconsistent system parameter that causes unexpected behavior during IPL.
- Security Rules: RACF or ACF2 rules for a resource are updated on one LPAR but not synchronized across