Exception Management: A White Paper
(Pre-requisites: SAP Solution Manager 7.1 SP05 or higher and ST-PI 2008_1 700 SP06 and higher)
In current changing business environments, more and more landscapes are coming up which want to integrate their legacy non SAP/SAP devices with state of the art SAP components. Thus, it is now imperative to have a smooth work flow among all kinds of devices and mitigate any error that may occur while integration of business processes. During day to day operations, it is likely that companies run into certain situations which are inexplicable and beyond their realm of normal operations but still need to be dealt with.
Need for Dedicated Exception Management
Before starting with Exception Management(ExMan) , lets first discuss what an exception really is:- “An Exception is the breaching of the normal assumed behavior ODF the system”. Here it needs to be stressed that exception is very different from error. Suppose a log has to be read from a file and the specified file is not present in the defined location than its an exception. If the log is read successfully and because of that there is a malfunction than that will be called as an error.
Logging all such exceptions and and pursuing them up to their closure requires a dedicated module which can be integrated easily with the available infrastructure and can also provide additional benefits .Here ExMan comes into picture which provides us various tools for monitoring and handling exceptions that may occur , resolving them in a timely manner.
Whenever a exception occurs in a process, it is necessary to retrace the steps that have caused that exception. ExMan provides us various procedures through which we can access the call trace , stack trace and other low level components to reach the root cause of that exception. Through ExMan we can define our own guided procedures to resolve certain exceptions. These guided procedures than can be used in the future whenever that exception may occur. We can monitor mission critical processes and by analyzing the trend values, we can estimate their next occurrences and avoid them .Through ExMan, we can also access those exceptions that are local in nature (e.g Web Service exceptions or ABAP dumps) i.e their occurrence only influences a single location and have influence only at this location. ExMan acts as a central hub for all kinds of exceptions occurring in the customer landscape.
ExMan is further constituted by :
Exception Monitoring Cockpit (EMC ) is a single point of access for identification and analysis for all single or multiple steps exceptions that may occur in customer landscape .One of the important feature of EMC is the monitoring of multiple steps exception which occur at a specific location but have influence over predecessor steps which have to be rolled back during exception handling. EMC provides a overview , across systems and technologies, of all process flow errors and technical exceptions that may have occurred. By default, it supports following types of single step exceptions to be monitored .
- SysLog errors
Web Service exceptions
For each type of exception, we can further create a detailed analysis report or can access the guided procedure specified to resolve the exception. Through EMC screen we can create notification of the exception or assign a processor to the exceptions.
For exception analysis, we can display the error context, the calling stack, the payload of the processing unit, and similar exceptions, in the detailed error description. For exceptions having multiple steps, information about each predecessor step is provided along with the interlinking and dependency present among the various steps of the process. This allows for fast and easy resolution of the exception as all the information is provided on a single screen.
Through exception alerting we integrate the monitoring and alerting infrastructure with exception management. We can retrieve context sensitive exceptions for TechMon from MAI. Generally exception values from system monitoring only contains statistical and historical data but the ExMan monitoring provides detailed in depth analysis per context of user, process or a category. The Alerts generated through this would collect into Alert Inbox
Guided Procedure Framework allows us to create our own procedures to handle the exceptions thatare caught during exception monitoring. We can create incidents or notifications from an exception or assign processors to them. The EMC screen provides link to the guided procedure browser.
Exception Management Instrumentation Platform
Sometimes it is necessary to define some critical points in the process which are sensitive to throwing exceptions and monitor them proactively. This can be achieved through ExMan Instrumentation Platform. For ABAP systems, it uses static code modifications and for Java systems,it uses Bytecode injection(dynamic instrumentation). It is present in the Solution tool plug-in , hence can be used independently.
Another important feature is its use of SAP Business Passport (BPP) to collect logging and tracing information for the programs currently running. It provides a unique token to the process instances for their identification in a business category and is passed from one step to another as the execution of the process continues. This allows us to trace and analyze all the steps that have occurred during the process execution in the defined business category.