Create an SSH Key (ED25519)
ssh-keygen -o -a 100 -t ed25519 -f ~/.ssh/id_ed25519 -C "$(whoami)@$(hostname)"Create an SSH Key (RSA)
ssh-keygen -t rsa -b 4096 -C "name@host-or-email"Copy SSH Public Key to Remote Host
ssh-copy-id -i ~/.ssh/your_custom_key.pub username@remote_hostCreate an SSH Tunnel
ssh -Nv -L target_port:endpoint:source_port user@host [-i ~/.ssh/some_ssh_key.xxx]Convert an id_rsa Key (PKCS#1 and PKCS#8) to an AWS-compatible PEM Key
openssl rsa -in ~/.ssh/id_rsa -outform pem > newfile.pem