Angus Robertson - Magenta Systems Ltd wrote: >> I guess that won't make a difference, since if a port were >> still in use an exception in Listen/Bind should be raised >> and CommandPASV() should return the error. > > There is a table in the server which keeps track of which passive > ports are in use, although it won't help if another application is > using the port.
This concept and the fact that passive listening sockets are created dynamically when a range is used may be a weak point, though that must not be the problem here. Btw: Serv-U opens one persistent listening socket per port in the range on startup, thus once they are listening no subsequent probs. with ports in use can happen. > >> Isn't it possible that winsock refuses the connection attempt due >> to a full ListenBacklogQueue > > Unlikely, these are Windows 2000 servers running IIS/5 FTP for five > years or so (and FileZilla) without any problems, I've only just > changed one to use ICS FTP server now it has mode z. > > Looking at more logs, I see: > > '501 Cannot RETR. Error - Connection reset by peer (#10054)' and > '501 Cannot RETR. Error - Connection aborted (#10053)' errors > are coming back as well for passive downloads. But they usually work > on the next attempt. Can you reproduce those errors in a simple environment that uses plain TCP/IP connections? Later today I will try as well. Arno -- To unsubscribe or change your settings for TWSocket mailing list please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
