Links

• man ssh-keygen
• SSH keypair generation: RSA or DSA?
  • Bottomline: RSA preferred now that patents have expired.
  • Also, if you can use ECDSA (elliptic curve dsa), it's stronger at lower bits (e.g. 521 bits) and is supported by OpenSSH 5.7+.
• Using multiple private keys
• SSH Keys

Examples

ssh-keygen -t rsa -b 2048

# -f for output file.
ssh-keygen -t ecdsa -b 521 -f id_ecdsa