I've been busy setting up a custom server-personality with Net::FTPServer
. Everything is running quite well but I've got a strange lingering bug with ACTIVE and PASSIVE connections.
Running linux I have no problems connecting via command-line ftp. Anyway, after the login, for example a "ls" fails with "504 Proxy FTP is not allowed on this server". Of course Proxy FTP is turned off due to security reasons - but as I understand it, I don't need Proxy FTP to just receive a dir listing. (btw turning Proxy FTP on to test if it solves the problem, just resulted in the client infinitely waiting for data.)
I've found out that switching the client into passive mode solves the problem. After that everything works just fine. But this workaround isn't satisfactory as my server can't tell any connecting client to go into passive mode (right?) and this leads to clients like gFTP connecting with default ACTIVE mode to fail on connects. As a note: my server is listening on a port above 1024.
Any hints what I am overseeing here?