What's New?

What's New in 3.7.4?


  • Hot Folder processes are now multi-threaded, allowing other processes to continue in cases when periodic scans take a long time (>1 hour).
  • A new Hot Folder maintenance option enables updating passwords from the command line. This command provides a scriptable way to update passwords in cases when passwords must be updated frequently, such as for Aspera Shares authentication in which passwords must be refreshed every 30 days. See Managing Hot Folders.
  • Data is now encrypted in transit (using AES-128) by default when a new connection is created in the GUI.
  • Transfers with Microsoft Azure Files are now supported, including using Azure Files access keys and the ability to create connections to Azure Files storage in the GUI.
  • Increased server security with upgrades to the OpenSSH SSHD service.
  • A new command-line tool, aclean, is a fast method of deleting directories and files from local and object storage. Directories and files can be filtered based on their last modified times, and the tool supports doing a dry run to determine what content will be deleted. For information, see aclean Reference.


  • The -u option can now be used with ascp4 to specify user strings, such as pre- and post-processing variables.
  • Persistent ascp4 sessions are now supported by using the --keepalive option.
  • Improved ascp4 transfer stability.
  • Improved error handling including: 1) errors are reported to both the client and server, 2) if the destination does not have enough disk space to receive the transfer then the session now exits with an error message, and 3) if some files in a transfer session fail to transfer, the last failure is now reported in the A4 session status.

Node API

  • The Node API /ops/transfers now supports ascp4 transfers. Specify that a transfer should use ascp4 rather than ascp by adding the following line to a JSON request:
    "use_ascp4" : true
  • The Node API can now pass instructions on how FASP transfers handle symbolic links. If no method is specified, the default policy is now follow.
  • The logging thread to the kvstore database now times out after the FASP transfer session ends. The timeout period can be configured with a new setting, <activity_log_queue_timeout>, in aspera.conf.
  • Partial files reported by a /files/browse call can now be identified with the new "partial_file" : true attribute, allowing them to be processed separately from complete files. To enable this, the <partial_file_suffix> must be set in aspera.conf. Files with the resume suffix are still filtered out from the dictionary.

Watchfolder and Aspera Watch Service

  • Faster directory scanning by the Aspera Watch Service, particulary of directories that contain many (10,000s) subdirectories.
  • Watchfolders now supports IPv6 addresses. See Creating a Watch Folder and Configuring the Watch Folder JSON Configuration File.
  • Watchfolder can delete files from the source as soon as the file is successfully transferred, rather than waiting for the session to complete, by editing the Watchfolder configuration JSON file or by enabling it in Console (In the Console GUI, go to File Handling > Source deletion and select Automatically delete a source file after transfer of this file). See the FILE_TRANSFER_DELETE post-processing option in Configuring the Watch Folder JSON Configuration File.


  • The Sync guide in now included in the Enterprise Server, Connect Server, and Point-to-Point Client guides (see Aspera Sync). It includes new instructions for composing an async command (see Composing an Async Session) and an expanded troubleshooting section (see Troubleshooting Sync).
  • Improved handling of changing files by continuous Sync sessions when checksum is set to none; files that return a sharing violation error are now retried per --sharing-retry-max.
  • Access key authentication is now supported by using "Basic: token_string" as an argument for the -W option. For more information, see Sync with Basic Token Authorization.
  • The --dedup option can now be used in async commands even if it is not specified in the first run; however, --dedup is rejected if the first run does not use -k. The dedup index is created if it does not already exist, and if the database is large then this process can take some time.

Object Storage Support

  • Improved restart process of the Aspera License Entitlement Engine avoids rare race conditions that can cause ALEE to fail to restart. (CIM-683)
  • The maximum open file limit of Trapd is now 20,000, improving the robustness of connections to the Redis database.
  • Faster authentication to AWS S3 when using AWS assumed roles. Trapd can now get credentials from regional Amazon Security Token Service (STS) endpoints, rather than only the global endpoint. If the Enterprise Server is installed in an EC2 instance, the regional endpoint is retrieved automatically, otherwise the endpoint can be set in s3.properties or the docroot.
  • Trapd and custom Trapd plugins can now use different libraries. Each plugin has a definition file in which the class name of the plugin and its classpath can be set. The plugin can be given a simple name and set in the docroot by using the simple name, as ?plugin=simple_name.
  • Simplified s3.properties configuration due to AWS S3 infrastructure enhancements that no longer require host caching and selection to optimize transfer performance. The following settings are deprecated, and have no effect if present: aspera.httpclient.connections-per-host-hint, aspera.s3session.hostcache.enabled, aspera.s3session.hostcache.directory, aspera.s3session.hostcache.aliases.enabled, aspera.s3session.hostcache.ns-lookup.main, and aspera.s3session.dnsResolvePolicy.

Breaking Change

  • Activity event reporting can now be configured with a new aspera.conf setting, activity_event_logging. Prior to 3.7.4, activity event reporting was always enabled. As of 3.7.4, activity event reporting is disabled by default to improve server performance, and it must be enabled in order to query the Node API /events endpoint. Nodes that are added to Aspera Files must have activity event reporting enabled. To enable it, run the following command:
    asconfigurator -x "set_server_data;activity_event_logging,true"

    For more information, see Configuring for Aspera Files.