Host ubuntu
     HostName ec2-13-230-66-222.ap-northeast-1.compute.amazonaws.com
     User ubuntu
     IdentityFile ~/.ssh/ttk.pem
     ServerAliveInterval 300
     ServerAliveCountMax 10
     TCPKeepAlive yes

Host ubuntu2
     HostName ec2-13-230-66-222.ap-northeast-1.compute.amazonaws.com
     User ubuntu2
     IdentityFile ~/.ssh/ttk.pem
     ServerAliveInterval 300
     ServerAliveCountMax 10
     TCPKeepAlive yes