Tools for Monitoring and Troubleshooting FRS

Microsoft provides a number of tools for monitoring and troubleshooting FRS that vary in their ability to perform real-time monitoring and troubleshooting or point-in-time troubleshooting. These tools also vary in their complexity and installation requirements and are thus suited for specific scenarios. The following topics provide a brief overview of each tool and when to use it.


Ultrasound is a powerful monitoring and troubleshooting tool used to measure the health of FRS replica sets. Ultrasound shows health ratings and historical information about replica sets and allows administrators to monitor the progress of replication and detect problems that can cause replication to become backlogged or stopped. Ultrasound also provides drill-down views for troubleshooting and a framework for customizing alerts and views to suit your organizational needs.

Because Ultrasound requires the deployment of WMI providers on all servers to be monitored, Ultrasound is best suited for organizations that want to regularly monitor FRS, even when FRS is working normally. For more information about Ultrasound, see Ultrasound Overview.


Sonar collects broad statistics about servers in a replica set, allowing administrators to monitor traffic levels, backlogs, free space, and other issues. In addition to providing basic monitoring capabilities, Sonar can also be quickly deployed on a single server to identify FRS problems.

Sonar works well for small organizations do not need a dedicated monitoring system and for organizations that have not deployed Ultrasound. Sonar also works well in scenarios where you want to quickly identify FRS problems.

Sonar provides less detailed troubleshooting information compared to Ultrasound because Sonar provides information on a per-member level. Sonar is quite useful when you need to quickly get a view of the health of the distributed system and determine possible problem areas. For more information about Sonar, see Monitoring FRS Using Sonar.

FRS Diagnostics (FRSDiag)

FRSDiag replaces the Health_Chk tool used to collect information about FRS from various sources, including Active Directory, event logs, FRS debug logs, and more. FRSDiag provides a graphical user interface for choosing which information to collect and analyzes the results to identify common problems.

After FRSDiag completes its collection and analysis, you can review the errors that FRSDiag identified and the text files that contain the information that FRSDiag collected. You can also provide these text files to Microsoft Product Support Services for assistance in diagnosing and resolving replication problems.

FRSDiag is typically used as a diagnostic and troubleshooting tool, not a monitoring tool. It is often used with Sonar or Ultrasound as a way to diagnose an unhealthy replica member. For more information about using FRSDiag, see Troubleshooting FRS Using FRSDiag.

FRS Troubleshooter

This troubleshooting guide provides step-by-step procedures that help you find the root cause of a number of FRS problems. These procedures are the same as those used by Microsoft Product Support Services to solve FRS problems and include tasks such as verifying network connectivity and DNS, verifying Active Directory replication, and examining output from FRSDiag. If you are not familiar with these tasks, we recommend that contact Microsoft Product Support Services for assistance. To use the troubleshooter, see FRS Troubleshooter.

Perl Scripts

The Perl scripts TopChk, Connstat, and IoLogSum are available as part of the Windows Support Tools. These scripts parse through the output of Ntfrustil commands to create a summary of relevant FRS data that is useful when troubleshooting FRS. For more information about running these scripts and interpreting their output, see FRS Data Collection Scripts.