Update proftpd.conf

install/ubuntu/proftpd.conf

@@ -16,6 +16,7 @@ LogFormat                       default "%h %l %u %t \"%r\" %s %b"
 LogFormat                       auth    "%v [%P] %h %t \"%r\" %s"
 ListOptions                     -a
 RequireValidShell               off
+PassivePorts                    12000 12100
 
 <Global>
   Umask                         002