To connect to Virtual Machines created in the European Weather Cloud (EWC), you must first configure an SSH KeyPair in OpenStack. This keypair allows secure, password‑less access to your instances.

What is an SSH KeyPair?

An SSH KeyPair consists of:

• Private key — stays on your computer

• Public key — uploaded to OpenStack

OpenStack injects the public key into your VM so you can log in using your private key. For more information on SSH please refer to SSH and SSH Keys.

1. Create or Import an SSH Key

You can either create a new keypair or import an existing public key.

Import an existing public key

If you already have an SSH public key (e.g., ~/.ssh/id_rsa.pub), you can import it into OpenStack using the CLI (using cloud.yaml file, see also EWC OpenStack API access - Install and use Command-Line client):

$ openstack keypair create --public-key /path/to/public_key <key_name>

Replace:

• /path/to/public_key with the path to your .pub file

• <key_name> with the name you want to assign to the keypair

create a new SSH key (if you don’t have one)

You can generate a new SSH keypair locally:

ssh-keygen -t rsa -b 4096 -f ~/.ssh/my_ewc_key

This creates:

• my_ewc_key (private key)

• my_ewc_key.pub (public key)

Then import the public key (using cloud.yaml file, see also EWC OpenStack API access - Install and use Command-Line client):

openstack --os-cloud=openstack keypair create --public-key ~/.ssh/my_ewc_key.pub my_ewc_key

2. Verify the keypair in OpenStack

List your keypairs:

openstack --os-cloud=openstack keypair list

You should now see your imported or newly created key.