SSH keys and ssh-agent

Cheat sheet

• ssh-keygen -t ed25519 generate a pair
• ssh-copy-id user@host install it on the server
• ssh-keygen -l -f key.pub fingerprint
• chmod 700 ~/.ssh directory — owner only
• chmod 600 ~/.ssh/authorized_keys key file — owner only
• ssh-add ~/.ssh/id_ed25519 load into the agent
• ssh -i ~/.ssh/key -o IdentitiesOnly=yes host use a specific key