Using git to deploy code across multiple servers is a handy technique that works in pretty much any situation. That is, until you’re trying to deploy to an environment such as Amazon’s EC2 servers, which uses .pem files to login. In these situations, the simplest solution I’ve found is a rather ancient technique: SSH keys.
Step 1: Generate an SSH Key
Note: If you already have an ssh key then you can skip this step
$ ssh-keygen -t rsa
After you hit enter, you’ll get some messages similar to these:
Enter file in which to save the key (/you/.ssh/id_rsa):<br />
Enter passphrase (empty for no passphrase):<br />
Enter same passphrase again:<br />
Your identification has been saved in /you/.ssh/id_rsa.<br />
Your public key has been saved in /you/.ssh/id_rsa.pub.
Step 2: Add Your Key to Your Amazon EC2 Instance
Use the following command to copy your key to your Amazon EC2 instance.
/you/.ssh/id_rsa.pub is the location to your ssh key,
pem_file.pem is the .pem file you normally use to login, and
email@example.com is the user and hostname to your EC2 instance:
$ cat /you/.ssh/id_rsa.pub | ssh -i pem_file.pem firstname.lastname@example.org "cat >> .ssh/authorized_keys"