This tutorial shows a way to move data around between Research Cloud workspaces.
This method makes use of the ssh-related scp command, in the commandline.
For this exact example, at least the target machine should be a Linux workspace.
You have two VMs, "VM_a" and "VM_b".
You want to scp data from VM_a to VM_b.
From your local computer, you can ssh into both VMs.
Approach
We cannot use ssh-copy-id because password authentication is switched off for security reasons. That's why we have to copy the public key to VM_b by hand.
Also, the ~/.ssh/authorized_keys file gets reset regularly on all machines for all Research Cloud users. So we have to create an extra user on VM_b that is not affected by this.
Steps
On VM_a
Create a ssh key-pair with
ssh_keygen
(when prompted for something just hit ENTER: no special name, format or passphrase)
Now VM_a has its own key-pair. Totally independent of the key-pair on you local machine.
Output the public key with
cat ~/.ssh/id_rsa.pub
Copy this public key into your clipboard
On VM_b
Create a user for data transfer
sudo useradd -m data-transfer-user
(the -m option also creates a homedir for this user)
sudo passwd data-transfer-user
Add the public key of VM_a for this user
sudo nano /home/data-transfer-user/.ssh/authorized_keys
From your clipboard, copy the public key of VM_a into the opened file "authorized_keys".
nano usage:
(ctrl+O for save, ENTER for confirm, ctrl+X to quit)
If you want to prepare particular folders in the data-transfer user's home, become that user, create the folders and go back to your regular user, again:
su data-transfer-user
mkdir ~/my-data-there
exit
On VM_a
You can test the ssh connection with
ssh data-transfer-user@VM_b
and end the test with
exit
Transfer your data
scp ~/my-data-here/* data-transfer-user@VM_b:~/my-data-there
Now the data should have been copied to vm_b.