ascp: Transferring from the Command Line with Ascp
Ascp is a scriptable FASP transfer binary that enables you to transfer to and from
Aspera transfer servers to which you have authentication credentials. Transfer settings are
customizable and can include file manipulation on the source or destination, filtering of
the source content, and client-side encryption-at-rest.
Ascp Command Reference
The ascp executable is a command-line FASP transfer program. This reference describes ascp syntax, command options, and supported environment variables.
Ascp General Examples
Use the following Ascp examples to craft your own transfers.
Ascp File Manipulation Examples
Ascp can manipulate files and directories as part of the transfer, such as upload only the files in the specified source directory but not the directory itself, create a destination directory, and move or delete source files after they are transferred.
Ascp Transfers with Object Storage and HDFS
Ascp transfers to and from servers in the cloud are similar to other Ascp transfers, though they might require explicit authorization to the storage as an authorization token or storage credentials.
Using Standard I/O as the Source or Destination
Ascp can use standard input (stdin) as the source or standard output (stdout) as the destination for a transfer, usually managed by using the Aspera FASP Manager SDK. The syntax depends on the number of files in your transfer; for single files use stdio:// and for multiple files use stdio-tar:// . The transfer is authenticated using SSH or a transfer token.
Using Filters to Include and Exclude Files
Filters refine the list of source files (or directories) to transfer by indicating which to skip or include based on name matching. When no filtering rules are specified by the client, Ascp transfers all source files in the transfer list; servers cannot filter client uploads or downloads.
Symbolic Link Handling
Creating SSH Keys (Command Line)
Reporting Checksums
File checksums are useful for trouble-shooting file corruption, allowing you to determine at what point in the transfer file corruption occurred. Aspera servers can report source file checksums that are calculated on-the-fly during transfer and then sent from the source to the destination.
Client-Side Encryption-at-Rest (EAR)
Aspera clients can set their transfers to encrypt content that they upload to a server while it is in transit and stored on the server, a process known as client-side encryption-at-rest (EAR). The client specifies an encryption password and the files are uploaded to the server with a .aspera-env extension. Anyone downloading these .aspera-env files must have the password to decrypt them, and decryption can occur as the files are downloaded or later once they are physically moved to a computer with no network connection.
Comparison of Ascp and Ascp 4 Options
Many command-line options are the same for Ascp and Ascp 4; however, some options are available for only one or the behavior of an option is different. The following table lists the options that are available only for Ascp or Ascp 4, and the options that are available with both. If the option behavior is different, the Ascp option has ** added to the end and the difference is described following the table.
Ascp FAQs
Answers to some common questions about controlling transfer behavior, such as bandwidth usage, resuming files, and overwriting files.