Application Checker Modernization Guide

Application Checker is a z/OS-based tool that automatically monitors the availability of TCP/IP applications. It attempts to establish TCP connections to remote applications to verify their availability and records response times. The tool also generates reports on unavailable resources.

Application Checker is an application and a tool set. It provides a specific function (application availability monitoring) and offers tools for reporting and analysis of that data.

Organizations that rely on z/OS and need to ensure the continuous availability of TCP/IP applications would benefit from Application Checker. This includes enterprises in industries such as banking, finance, insurance, and any business with critical mainframe-based applications.

A company should consider using Application Checker when they experience disruptions or need proactive monitoring of TCP/IP application availability on z/OS. It is particularly useful when application downtime directly impacts business operations or revenue.

Alternatives to Application Checker include general-purpose network monitoring tools, application performance monitoring (APM) solutions, and custom scripting. However, these may not be specifically designed for z/OS or provide the same level of integration with the mainframe environment.

Application Checker requires a z/OS environment with TCP/IP configured. It needs the ability to open TCP connections to remote applications. Historical data is stored, so a suitable storage mechanism is also required.

Application Checker runs in an LPAR on z/OS. It is dependent on the z/OS operating system and its TCP/IP stack. It may require specific subsystems depending on the storage mechanism used for historical data.

Application Checker is typically deployed on-premise within the z/OS environment. It requires technical expertise to configure the TCP/IP connections and interpret the reports.

The exact syntax for basic operations depends on the specific implementation of Application Checker. However, a typical operation would involve specifying the target IP address and port number of the application to be checked. For example, a configuration file might contain entries like 'APPLICATION=MYAPP, IP=192.168.1.100, PORT=8080'.

Application Checker provides business value by proactively identifying application availability issues before they impact users. This reduces downtime, improves service levels, and prevents potential revenue loss.

If an organization did not use Application Checker, they would likely rely on reactive measures to identify application availability issues. This could lead to longer periods of downtime, increased user frustration, and potential business impact.

Application Checker integrates with enterprise ecosystems by providing data on application availability that can be used by other monitoring and management tools. It can also generate alerts that are sent to operations teams.

Specific authentication methods supported by Application Checker depend on the z/OS environment and configuration. It may leverage RACF, ACF2, or Top Secret for authentication. The access control model is likely based on ACLs within z/OS.

Encryption used by Application Checker depends on the configuration of the z/OS TCP/IP stack. Data transmitted between Application Checker and the monitored applications may be encrypted using TLS/SSL.

Application Checker provides audit and logging capabilities by recording the results of application availability checks. This data can be used to track trends, identify problems, and demonstrate compliance.

Ongoing operational requirements for Application Checker include monitoring the tool itself, maintaining the configuration of TCP/IP connections, and reviewing the reports generated by the tool. Staffing requirements depend on the size and complexity of the environment.

Common implementation challenges for Application Checker include configuring the TCP/IP connections correctly, ensuring that the tool has the necessary permissions to access the monitored applications, and interpreting the reports generated by the tool.

Administrative interfaces available for Application Checker depend on the specific implementation. It may include a CLI, a GUI, or a web console. User management is typically handled through z/OS security mechanisms.