18. Configuring SSH Key-based Authentication on Ubuntu

When an Ubuntu system is first installed, it is not configured by default to allow remote command-line access via Secure Shell (SSH) connections. When installed, SSH provides password protected and encrypted access to the system for the root account and any other users added during the installation phase. This level of security is far from adequate and should be upgraded to SSH key-based authentication as soon as possible.

This chapter will outline the steps to increase the security of an Ubuntu system by implementing key-based SSH authentication.