NO-OP command required for large downloads/uploads?

Question

Hi,

Does edtftpj (free version) automatically issue NO-OP commands during file upload/downloads when a pre-set time-out interval has reached?

Or is it even necessary to issue a NO-OP command when downloading/uploading huge files?

Or should the KeepAlive() Function be used instead?

Thanks.

Answer 1

By default it doesn't do this. If you call setServerWakeupInterval(30) it will send NOOPs every 30 s.

Some servers go to sleep when transferring large files, so this technique can sometimes work. Often though it can hang the server. KeepAlive() just sends one single wakeup operation, it doesn't do it repeatedly.

Answer 2

I use the free version of the edtFTPj to transfer big files (over 6 GB) with a maximum bandwidth of 240 kB/sec and sending NOOP was not required. (At least using the proftpd server)

Answer 3

ProFTPd and PureFTPd seem to be nice with large transfers, they never kick you out as long as either the control or data connection is active.

But vsFTPd constantly drops me out after 3 minutes of transfer time. Their documentation states that it will kick you out if the control connection is in-active regardless of the data connection's activity.

Answer 4

Which is just bad coding really. Obviously the server knows a file is being transferred - the timeout should only apply to the control connection when nothing is being transferred.