This lecture requires practical exercises. Each group will have access to two virtual machines for mimicking client-provider and replication scenarios.

If you do not yet have a public/private ssh key pair the ssh-keygen command is your friend. It allows for generating a pair inside your ~/.ssh subdirectory. Working on a network drive your first problem may be inappropriate file permissions of and inside your ~/.ssh directory:

The permissions of the directory itself and the files within are too open . The sshd daemon will deny remote access due to possible security implications. Unfortunately the standard chmod command from UNIX does not suffice on modern cifs based network file systems using extended ACLs. The getfacl command reveals details:

The counterpart setfacl allows for revoking permissions e.g. on authorized_keys:

Addressing each file and the directory itself in a similar fashion leads to:

You should now be able accessing your virtual machines: