Enabling SSH access
Acquia Cloud creates a Unix user account for each website called the site user. The website's Drupal/PHP code runs as this user, and all of a site's environments (Development, Staging, and Production) use the same Unix user. If there are multiple sites on a single web server, Unix security permissions keep them isolated from each other, because each site runs as a different Unix user.
To use SSH to log into your web server as the site user, register SSH public keys for your Acquia user profile. You can add as many SSH keys as you want, each with its own nickname to help you keep track of them. However, you always log in to the server as the site user's Unix username. The SSH key nickname is not a Unix username; it is just for your convenience in identifying your SSH keys.
When you SSH in to your Acquia Cloud server, always SSH to the full DNS name of your server and not to your website URL host name. To view your web servers, sign in to the Acquia Cloud UI, select your website, and then go to the Servers page at Cloud > Servers. The following list provides sample host names: