Aspera CLI

This guide walks you through installing, configuring, and using the Aspera Command Line Interface (ascli) on Rockfish to download files from the JHG Aspera server.

Start an Interactive Session (Optional)

Start an interactive session if you plan to run downloads from a compute node:

interact -p shared -n 6 -t 02:00:00

Install ascli

Load the Ruby module:

module load Ruby/3.1.2

Install `aspera-cli`:

gem install aspera-cli --user-install

Add `ascli` to your PATH:

Note

Confirm the installation path of ascli. It should be either: $HOME/.gem/ruby/3.1.0/bin or $HOME/.local/share/gem/ruby/3.1.0/bin.

echo 'export PATH="$HOME/.local/share/gem/ruby/3.1.0/bin:$PATH"' >> ~/.bashrc
source ~/.bashrc

Note

✅ You only need to do the installation and path configuration once.

Configure ascli

Load the Aspera Connect module and start SSH agent:

module load Aspera-Connect/4.1.1
eval "$(ssh-agent -s)"

Run the configuration wizard:

ascli config wizard

When prompted, enter the following:

argument: url (e.g:)> https://jhg-aspera2.jhgenomics.jhu.edu
option: username> Your JHG Aspera username (e.g., your JH email)
option: password> Your JHG Aspera password

Downloading Data

Use the following command to download data (replace placeholders with your actual credentials):

ascli shares files download \
  --url=https://jhg-aspera2.jhgenomics.jhu.edu \
  --username=your@email \
  --password=XXXXXXX \
  /cidr-newby/U6-MPRA-1 \
  --ts=@json:'{"target_rate_kbps":300000,"resume_policy":"sparse_csum"}'

Using ascli in the Future

Next time you need to use ascli, simply run:

module load Ruby/3.1.2
module load Aspera-Connect/4.1.1
eval "$(ssh-agent -s)"

Then you’re ready to use ascli again.