Document that request buffering is required for PUT (#31)

* Document that request buffering is required for PUT

* Move to new "Server requirements" section

---------

Co-authored-by: Ricki Hirner <[email protected]>

Author: sunkup

webdav_mounts.rst

@@ -16,6 +16,18 @@ A WebDAV mount allows you to work with remote folders and files of a WebDAV serv
 .. youtube:: FwfwNXFtvYE
 
 
+Server requirements
+===================
+
+WebDAV mounts should work with any compliant WebDAV server.
+
+When using HTTP/1.1, DAVx⁵ uses chunked transfer encoding for PUT requests because it doesn't know the
+file size in advance. This requires some servers to be configured for request buffering. Otherwise resulting
+files may always have 0 bytes or a 411 Length Required error is returned. Using HTTP/2 may avoid this.
+`sabre/dav recommends <https://sabre.io/dav/0bytes/>`_ to use Apache with mod_php (not FastCGI) or a
+recent version of nginx and to avoid Lighttpd.
+
+
 Restrictions
 ============