SSH

Secure Shell (SSH) is a protocol that allows for remote login to operate securely over unsecure networks. SSH uses public key cryptography for authentication.

Generating SSH key

SSH keys are a way to identify trusted machines without involving passwords. SSH key can be generated and added to GitHub account for example.

ssh-keygen -t rsa -b 4096 -C "ktpeng@uwaterloo.ca" Creates a new ssh key using email as a label. Follow prompts.

Adding

• eval "$(ssh-agent -s)" ensures ssh-agent is enabled.
• ssh-add ~/.ssh/filename

Add to GitHub

• Navigate to Settings/ssh keys
• open ~/.ssh/id_rsa, copy

To copy to clipboard:

$ sudo apt-get install xclip
# Downloads and installs xclip. If you don't have `apt-get`, you might need to use another installer (like `yum`)

$ xclip -sel clip < ~/.ssh/id_rsa.pub
# Copies the contents of the id_rsa.pub file to your clipboard

Checking existing SSH keys

ls -al ~/.ssh checks for existing SSH keys.

By default, filename should be one of the following:

• id_dsa.pub
• id_ecdsa.pub
• id_ed25519.pub
• id_rsa.pub