The introduction of the FAST search engine in SharePoint 2010 has made SharePoint a serious contender in the search space, but has also increased the complexity of a SharePoint deployment.

So if you want to become a FAST expert, or diagnose an existing installation, where should you start?

Firstly, the content on MSDN is invaluable in understanding FAST. It's especially important to understand how the search service applications (SSAa) work, what options they provide, and what services are provided by fast itself, not the SSAs.

There is a good suite of developer training videos available for free.

To understand the internals of how FAST works, I suggest reading Microsoft's protocols specification for the product [MS-FSO].

In my experience a common problem is related to service accounts and permissions. Make sure you get these right!  If FAST services just won't start up  - as reported by the nctrl command - this is usually the cause.

It is critically important that you verify your deployment, follow the instructions here: Verify successful installation (FAST Search Server 2010 for SharePoint).

You can test various parts of the FAST engine using powershell scripts. The docpush tool, for example, can be used to test FAST's ability to index an item.  There is a powershell script at the bottom of this page which tests FAST's search query refinment functionality. It provides a good starting point for writing other testing scripts to interact with the query side of FAST Search.

A SCOM management pack is available for FAST; naturally Microsoft recommends using this to monitor your FAST deployment. (More about SCOM design in a coming blog post..)

For more information about FAST, WROX press has published "Professional Microsoft Search: FAST Search, SharePoint Search, and Search Server", authored by Mark Bennett, Jeff Fried, Miles Kehoe, Natalya Voskresenskaya. I haven't read it yet but will provide a review when I do.