308 Permanent Redirect

The HTTP 
308 Permanent Redirect redirection response status code indicates that the requested resource has been permanently moved to the URL given by the Location header.
A browser receiving this status will automatically request the resource at the URL in the 
Location header, redirecting the user to the new page.
The request method and the body will not be modified by the client in the redirected request.
A 301 Moved Permanently requires the request method and the body to remain unchanged when redirection is performed, but this is incorrectly handled by older clients to use the GET method instead.
NOTE:
Some Web applications may use the 
308 Permanent Redirect in a non-standard way and for different purposes.
For example, Google Drive uses a 
308 Resume Incomplete response to indicate to the client when an unfinished upload has stalled.
See Perform a resumable download on the Google Drive documentation for more information.
Status
308 Permanent Redirect
Examples
308 response to a moved resource
GET /featured HTTP/1.1
Host: www.example.org
HTTP/1.1 308 Permanent Redirect
Location: http://www.example.com/featured
Content-Length: 0
Specifications
Browser compatibility
See also
Redirections in HTTP
HTTP response status codes
301 Moved Permanently, the equivalent of this status code that may modify the request method when it is not a GET
302 Found, a temporary redirect