If you have to connect to a number of EC2 machines, typing a long command that looks like the following each time can be painful.
ssh -i /somepath/somefile.pem firstname.lastname@example.org
A way to make this command much shorter is by using SSH config file.
Edit (or create) file ~/.ssh/config
Now for each EC2 server that you connect to, add a section that looks like this…
Host test1 HostName 100.100.100.100 User ec2-user IdentityFile /User/name/ec2pems/test1.pem
Now you can connect to the instance by typing a command that looks like this…