10.5.10 Resume an Incomplete Server File Download

Sometimes when downloading a server file to your PC, the transfer does not complete successfully, perhaps due to a loss of the network connection on a "noisy" or low-speed link.

NOTE:This feature is not available for SFTP connections.

When a file transfer fails to complete, the auto resume feature lets you resume the incomplete file transfer operation. The auto resume feature works only under these circumstances:

  • The FTP server must support the REST command

    To auto resume a file transfer, the FTP Client sends a REST command (restart) to the server. If the server does not support the REST command, the file transfer will start from the beginning of the file. For each site, after the first auto resume operation is attempted, the FTP Client will remember the result. If the server does not support the REST command, the Client won't attempt to perform an auto resume for any file transferred from that server.

    To determine if a particular server supports this feature, enter the following on the command line:

    quote help rest

    If rest is identified as a restart command, your server supports the feature

  • File transfer method (or type) must be Binary

    Auto resume compares the size of the source file to the size of the incomplete target file to determine at what point in the source file it should resume the transfer. An ASCII file transfer creates a file on the local machine that may differ in size from the source file.

  • File transfer mode cannot be Append

    When you transfer a file using the Append mode, the FTP Client can't use the existing target file size to determine the restarting point to use in the source file.

To resume an incomplete download

  1. If necessary, reconnect to the server where the source file resides.

  2. Confirm the three circumstances above.

  3. From the Transfer tab of the Site Properties dialog box, select Try to resume partial binary downloads.

  4. Restart the server file download. For example, select the server file that failed to transfer and drag it again to the destination on your PC.

  5. The client detects that a prior incomplete file transfer operation occurred for that file, and gives you the option to resume the incomplete transmission at the interruption point, instead of beginning a new file transfer of the entire file.

  6. Click Resume.