The error-fastcgi is an Error function. The error-fastcgi SAF handles the errors specific to the FastCGI plug-in. This function however does not handle the HTTP errors. On error, FastCGI plug-in can be configured to display a specific page or redirect the request to a specific URL.
The list of parameters accepted by error-fastcgi SAF, are available at: FastCGI SAF Parameters.
The following obj.conf snippet demonstrates the use of error-fastcgi:
Error fn="error-fastcgi" error-reason="Invalid Parameters" error-url="http://www.foo.com/errorPage.html"
See FastCGI SAF Parameters for information on the error-fastcgi parameters.