When trying to crawl a PHP based web site, the SharePoint crawler (with FAST backend) only processes the first page and will not follow any links thereafter. The "normal" SharePoint crawler (not connected to a FAST backend) crawls this site without error.
The PHP extension is not added to the list of extended connector (FAST connector) property.
Add the file extension PHP for the FAST connector using 'Set-SPEnterpriseSearchExtendedConnectorProperty'.
First get the current value for the extended connector (FAST connector) property using the following PowerShell command:
Get-SPEnterpriseSearchExtendedConnectorProperty –SearchApplication $searchApp –identity ExtensionsToFilter where $searchApp is the Fast connector Search Service Application (SSA).
The value returned would be something like “;ascx;asp;aspx;htm;html;jhtml;jsp;”.
Then set the value using for the extended connector (FAST connector) property using the following PowerShell command