Download SSH Key Identity File

Cluster administrators can create an SSH key pair when creating a cluster in Cloud Center. This key pair allows the administrator to log into to the clusters as ubuntu (sudo). For details about SSH key pairs, see the AWS^® documentation on Amazon EC2 key pairs.

To allow other users of a cluster to transfer data between their local machines and the cloud cluster, the cluster administrator must grant these users access by either creating an SSH key pair or a password for the user. After you have granted access to the clouduser, they can use any of the file transfer utilities described in Transfer Data with Standard Utilities to transfer data between their local machine and the cluster.

Create SSH Key Pair for Cluster Administrator

When you create a cluster in Cloud Center, you must provide an SSH key. Amazon^® Web Services (AWS) requires an SSH key in that region to start Amazon EC2^® instances. You also need this key if you want to log in as ubuntu (sudo) to your cloud cluster machines.

If you have existing keys, select from the keys for the specified region of your AWS account. By default, Cloud Center uses the previously selected key or the first key listed alphabetically in the AWS account.

If you do not have an existing key, you can create a new one in Cloud Center. On the Create Cloud Resource page, click Create new in the Name of SSH Key cluster setting. In the dialog box, enter a name, and click Download Key. Your browser might require you to identify a location. You get a root access key file with the extension .pem. Store this file in a safe place, because you cannot download it again. You can specify the same SSH key for multiple clusters.

Create SSH Key Pair for Cluster Users

This section shows how a cluster administrator can create an SSH key pair for a cluster user to allow them to access the cluster. To create a password instead, see Create Password for Cluster Users.

1. Go to AWS portal and create an SSH key pair for your user, clouduser. For details, see the AWS documentation on Amazon EC2 key pairs.

2. Retrieve the public key of the SSH key pair you created for clouduser. For details, see the AWS documentation on Retrieve the public key material.

3. Connect to the cluster head node using SSH as the ubuntu user and the SSH key pair you used when you created a cluster. Use the -i option to select the SSH private key of the ubuntu user for authentication in /path/to/private_key.pem. Replace <headnode-ip-address> with the IP address of the headnode of your cluster.

   ssh -i /path/to/private_key.pem ubuntu@<headnode-ip-address>

4. Switch to the clouduser account using sudo.

5. Create the folder /home/clouduser/.ssh and set permissions so that only clouduser can access this folder.

6. Paste the contents of the public SSH key you created for clouduser into the file authorized_keys inside this folder.

7. Share the private key of the SSH key pair with the user who can log in as clouduser. This is the private key of the SSH key pair you created for clouduser.

Create Password for Cluster Users

This section shows how a cluster administrator can create a password for a cluster user to allow them to access the cluster. To create an SSH key pair for the user instead, see Create SSH Key Pair for Cluster Users.

1. Connect to the cluster head node using SSH as the ubuntu user and the SSH key pair you used when you created a cluster. Use the -i option to select the SSH private key of the ubuntu user for authentication in /path/to/private_key.pem. Replace <headnode-ip-address> with the IP address of the headnode of your cluster.

   ssh -i /path/to/private_key.pem ubuntu@<headnode-ip-address> 

2. Once logged in as the root user, create a password for a non-root user, say clouduser using this command on the terminal.

   sudo passwd clouduser