Increase client_body_buffer_size and client_max_body_size to 16K

nginx.conf

@@ -53,9 +53,13 @@ http {
 
         # client_body_buffer_size and client_max_body_size should match, to
         # ensure the $request_body will have data.
-        # (8K is the default buffer size, and probably more than enough for log messages.)
-        client_body_buffer_size 8K;
-        client_max_body_size 8K;
+        #
+        # We started with 8K, which is the default buffer size, and learned that
+        # some POSTs were 9-10K. To check whether the size is too small for your
+        # application, look for log messages from your log-shipper app with the
+        # text "client intended to send too large body"
+        client_body_buffer_size 16K;
+        client_max_body_size 16K;
         lua_need_request_body on;
 
         if ($request_method = POST) {