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Find answers to frequently asked questions about Transfer.
Transfer is a standalone file transfer server, not a client. The client is responsible for initiating the file download or upload request.
Devices that use TFTP, HTTP, FTP, or SFTP to update or recover their firmware operate in one of two modes. In one mode, the device acts as a server, and it expects a client to upload the firmware to it when indicated. In the other mode, the device acts as a client, and it expects a server that can be used to download the firmware from it.You can only use Transfer to update or restore the firmware of a device that acts as a client, expecting to download the firmware file from a server, in this case, Transfer.

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TFTP

To allow TFTP traffic through a network firewall, you must create two rules:
  • The first rule passes all UDP traffic from the client to your Mac. The client makes the first connection to the Mac on port 69, but it will then make a second connection on a random destination port.
  • The second rule passes all UDP traffic from your Mac back to the client, irrespective of the ports involved because Transfer will respond with a random source port.

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HTTP/HTTPS

To allow HTTP or HTTPS traffic through a network firewall, you must add a rule that allows TCP traffic from the client to your Mac on port 80 for HTTP, or port 443 for HTTPS.

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FTP

To allow FTP traffic through a network firewall, you must create two rules:
  • The first rule allows TCP traffic from the client to your Mac on port 21. If using PASV mode, you also must allow inbound TCP traffic on the passive port range configured in Transfer (50000-51000 by default).
  • The second rule allows TCP traffic from your Mac back to the client on the same passive port range.

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SFTP

To allow SFTP traffic through a network firewall, you must add a rule that allows TCP traffic from the client to your Mac on port 22.

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See also