I've tried to clarify the behavior; see: http://www.proftpd.org/docs/modules/mod_core.html#SocketBindTight
If you are have: SocketBindTight on And proftpd receives a connection for which there is no <VirtualHost> configured, the client will receive this response 500 Sorry, no server available to handle request on xxx.xxx.xxx.xxx. EXCEPT if your proftpd.conf has "DefaultServer on" somewhere. If DefaultServer IS used, then that <VirtualHost> (or "server config") section bearing the "DefaultServer on" setting is used to handle that connection -- that's what the DefaultServer directive is for. Thus if your "SocketBindTight on" configuration is not causing clients to receive the "no server available to handle request" when they try to connect to an unconfigured IP address/port, then it says that your proftpd.conf is using DefaultServer somewhere. Cheers, TJ
