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If a hard drive is present in the firewall that supports reporting its status by [https://en.wikipedia.org/wiki/S.M.A.R.T. S.M.A.R.T.], it can be viewed by visiting Diagnostics > SMART Status.
The most common views to use are:
Health report, which provides a simple pass/fail of the drive status
Attributes, which lists the individual S.M.A.R.T. data points
All, shows all available information
Drive tests may also be initiated, and the results of the tests may be viewed. These tests can be performed while the system is running, but may impact performance of disk operations during the test.