ftp.ntua.gr:/mirror/ubuntu/dists/groovy/main/debian-installer/binary-amd64/by-hash/SHA256/?C=N&O=A 
Icon  Name                                             Last modified      Size  Description
[DIR] Parent Directory                                                      -   
[   ] 4857f472e496da8349fa25ce01ff4d2a165b8a6061a53..> 19-Oct-2020 21:05  8.3K  
[   ] 5d1c90fef6c8016456d14b7fd7f63f355a83ceff053cf..> 19-Oct-2020 21:05  7.4K
Apache/2.2 Server at ftp.grnet.gr Port 80