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Is there any open source/commercial FTP client which supports FTPS (FTP over SSL/TLS) over firewall/proxy? Since If we use SSL/TLS, the Control channel is encrypted and the Firewall couldn't understand the port used for data communication. But, If we use passive mode, is this limitation can be addressed?

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It depends which end the firewall is on. If it's on the client machine, it usually is possible to just allow any connections made by the FTP client application.

If the firewall is elsewhere, you will have to manually open the ports used – some FTP servers allow specifying a range of ports to use for passive-mode data transfers (same for FTP clients when in active mode), which you could open; for example, 50000-50100. Other than that, there is no sane way for FTPS to work behind a firewall.

(There exist FTP proxies/firewalls that decrypt the TLS stream (essentially performing a man-in-the-middle attack) to snoop on FTP PORT/PASV commands, but I personally have a strong dislike for those.)

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