About diagnostics

The Diagnostic Monitor

The Diagnostic Monitor is a set of diagnostics tools and tests that is used to search for and determine hardware problems. It is used as part of system troubleshooting to help isolate and identify a faulty component or to confirm that a specific component is operating properly.

When to run diagnostics

Typically, you run diagnostics after one of the following events happens on your system:

System panic is caused by an unidentified hardware failure
Access to a specific device becomes intermittent or the device becomes unavailable
System response time becomes sluggish

The following scenarios are examples of when you might run diagnostics:

After the initial hardware installation

When you install your system for the first time, before you boot it, you can check the hardware components by running the all diagnostic. If any problems exist at the hardware level, you can learn about them before you boot the system and connect it to the network.

When the system fails

When the system fails, test the system by first running the all diagnostic and then running individual diagnostics to isolate the cause of the failure.

When adding or replacing hardware

When you add new hardware, such as disk shelves, or change hardware components, before you boot the system, run individual diagnostics, such as fcal, to make sure that the disk shelf connections are sound.

When you replace a suspect component, run an individual diagnostic on the new component to check it before you boot the system. If the problem persists, it is not caused by the suspect component, but lies somewhere else.

If you suspect a problem in a specific hardware area

For example, you observed a lot of error messages of a specific type that point to a problem with the FC-AL connection. This should lead you to run the fcal comprehensive diagnostic while the system is running. If the system passes all tests except for the two tests that require a loopback plug, you might disconnect the system at an appropriate time and run the Loop integrity and Read-only bus tests in extended mode.

Another example is a CPU fan error causing Data ONTAP� software to panic and shut down the system. When you examine the fan and see that it is spinning, a specific test of the fan might show that the fan is not spinning at the right speed. Replacing the CPU fan should solve the problem.