SSH key that uses Ed25519 algorithm

Ready for a new key? You should be.

The Ed25519 was introduced on OpenSSH version 6.5. It’s the EdDSA implementation using the Twisted Edwards curve. It offers a better security with faster performance compared to DSA or ECDSA. Some benefits:

Its faster, and compact – it only contains 68 characters, compared to RSA 3072 that has 544 characters. Generating the key is fast! It’s also fast to perform batch signature verification with Ed25519.

To generate a new SSH key that uses Ed25519 algorithm, run:

# ssh-keygen -o -a 100 -t ed25519 -f ~/.ssh/id_ed25519 -C ""

Enter a strong passphrase.

Adding Your Key to SSH Agent

# eval "$(ssh-agent -s)"

Then run the following command to add your newly generated Ed25519 key to SSH agent:

# ssh-add ~/.ssh/id_ed25519

Add a config file for easy access. Add an entry to the ~/.ssh/config file to configure these options:

Host myserver
User roger
IdentityFile ~/.ssh/id_ed25519
IdentitiesOnly yes


# ssh myserver