This behavior is dictated by the CGI specifications.

The CGI environment variable specifications document that the variable REMOTE_HOST does not always get set. Typically this can happen for local requests on ip 127.0.0.1.

You probably want to use REMOTE_ADDR as a more reliable reference. It returns an IP address though.

In reply to Re: Retrieving the REMOTE HOST by varian
in thread Retrieving the REMOTE HOST by Anonymous Monk

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