ED25519 sshkey

gistfile1.txt

KEY_NAME=MY-SECRET_KEY; ssh-keygen -t ed25519 -a 100 -N "" -f ~/.ssh/"${KEY_NAME}" -C "${KEY_NAME}"

# Explanation
KEY_NAME=MY-SECRET_KEY      The name of the key, also used as filename
-t ed25519                  Use a ed25519 key
-a 100                      Use 100 key derivation function rounds (higher = slower)
-N ""                       No password
-f ~/.ssh/"${KEY_NAME}"     Store the key at this location on your computer
-C "${KEY_NAME}"            Set the comment to the key name

ssh_config

Host *
  Protocol 2
  CheckHostIP yes
  StrictHostKeyChecking ask
  ForwardAgent no
  IdentityAgent none
  ForwardX11 no
  HostbasedAuthentication no
  GSSAPIAuthentication no
  GSSAPIDelegateCredentials no
  PermitLocalCommand no
  Tunnel no
  Compression yes
  Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
  MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256
  KexAlgorithms curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
  ServerAliveInterval 60

Host github.com
  Hostname github.com
  User git
  BatchMode yes
  IdentityFile ~/.ssh/github-key
  PasswordAuthentication no
  IdentitiesOnly yes