What's missing from ASP.NET Health Monitoring and ELMAH?

In our previous post, we provided an example of a security issue that could not be diagnosed solely with event details collected by ASP.NET health monitoring. Some developers have asked us about the open source Error Logging Modules and Handlers (ELMAH) and how that would have helped in this same situation.

ELMAH is becoming a popular tool for error logging. Many find it more flexible and easier to use than ASP.NET health monitoring. Both tools provide good visibility into application health state changes, including start, shutdown, heartbeat, audit messages, etc. ELMAH extends the exception problem details available via health monitoring to include the ability to log error data from custom error handlers.

The ELMAH API also provides support for different data storage methods and web-based access for error data. In production environments, this data often helps improve and speed support team access to error data.

This information is very valuable for troubleshooting efforts. However, AVIcode's ability to collect runtime parameters that are passed through the methods in the call stack makes root cause diagnosis much easier and more straightforward than health monitoring and ELMAH. In addition, AVIcode's monitoring solutions provide greater visbility into all the problem details for both handled and unhandled exceptions, as well as performance problems. These details can also be consolidated and correlated with key performance counters over time to provide a more complete picture of application behavior and its effect on the IT environment.

One common example of a typical exception that is very difficult to diagnose with ELMAH or other standard error logging APIs is a NullReferenceException. For this (and all other) application problems, AVIcode collects the runtime parameters and member variable values, enabling analysis of the code stack and determination of the application health state. The screenshot below shows a typical example with the AVIcode collected data. 

In addition, AVIcode enables linking to the PDB file, even after data is collected in production, in order to show the source file name and precise line number where the exception occurred. This is accomplished without the PDB files needing to be deployed to a production server, which is typically against corporate IT policy and certainly not recommended. 

Another advantage that AVIcode provides over ELMAH is a secured, centralized web console for managing data access.  The AVIcode console can be integrated with Windows or Forms authentication and allows for differentiating access privileges based on logical hierarchies and account/application log access rules.  The console is web-enabled, so authorized users can view, search, filter and group data by various parameters. For example, grouping errors by unique issues, with a count of instances or occurrences, helps to eliminate the clutter created by multiple instances of the same error.