SSH is the most common way of connecting to remove Linux Server. It stands for Secure Shell. It provide a safe and secure way of executing commands, making changes and configuring service remotely. SSH connecting is implemented using client-server model. For a client machine to connect to a remote machine using SSH, SSH daemon must be running on the remote machine.
Clients generally authenticate either using passwords or by SSH Keys. SSH keys provides a more secure way of logging into a virtual private server using SSH. SSH keys are nearly impossible to decipher by brute force alone.
SSH keys are a matching set of cryptographic keys. Each set contains a public and private key. To authenticate using SSH keys, you place the public key on any server and then unlock it by connecting with the private key.
ssh-keygen -t rsa
ssh-copy-id user@123.45.67.89
Alternatively,
cat ~/.ssh/id_rsa.pub | ssh user@123.45.56.78 "mkdir -p ~/.ssh && cat >> ~/.ssh/authorized_keys"
Note - Generally when you spin up a server, you can embed your public key in your new server.
Option -y outputs the public key
ssh-keygen -y -f private-key > public-key
# Example
ssh-keygen -y -f pin-ost.pem > art.pub