SSH Public Key Setup

Verify the tilde@Cornell SSH Server

Before entering the join password, make sure SSH shows the correct tilde@Cornell server fingerprint.

The correct ED25519 host key fingerprint is:

If SSH shows a different fingerprint, do not continue. Your network may be redirecting cornelltilde.com, especially on school or managed networks.

If you previously accepted a wrong key, remove it and reconnect:

What You Need

Your application requires your SSH public key (not your private key). This allows secure passwordless login after approval.

Your account cannot be approved without it.

Check If You Already Have One

Most students already have one. First, check by running:

If you see files like id_ed25519.pub or id_rsa.pub, you already have a public key.

View and Copy Your Public Key

To view and copy your key:

If you only have id_rsa.pub, that works too.

Copy the full line and paste it into the tilde@Cornell application form.

Create a New SSH Key

If you do not already have one, create a modern SSH key with:

Then:

• Press Enter to accept the default file location
• Choose a passphrase if you would like one (recommended)
• Your public key will be saved as ~/.ssh/id_ed25519.pub

Helpful Documentation

Additional guides:

DigitalOcean: Create SSH Keys with OpenSSH
AWS: Creating SSH Keys on macOS, Linux, and Unix

Apply

Once your SSH public key is ready, return to the join server: