====== SSH 활용하기 ======


===== ssh 인증없애기 =====
  - host1에서 host2로 인증없이 접근을 한다고 가정하자.
  - host1 계정에서 ssh-key를 생성한다. <code>
starlits@host1:~/.ssh$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/starlits/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/starlits/.ssh/id_rsa.
Your public key has been saved in /home/starlits/.ssh/id_rsa.pub.
The key fingerprint is:
57:d0:5c:a5:3a:d7:18:90:11:57:62:f4:0a:69:d8:2d starlits@twasadmin
</code>
  - ~/.ssh 아래에 id_rsa.pub id_rsa 파일이 존재하는지 확인한다. <code>
starlits@twasadmin:~/.ssh$ ls
authorized_keys  id_rsa  id_rsa.pub  known_hosts
</code> <code>
$ cat id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAlAEudFqJh7JtdOW6Cv713kL1k0zyaOyzPeHPj4eQ7wjOj/ero5k4DCcmacm/CPvtLrPDsKxMQUdyQQ4cOnMNRYVNX2pZL/NuREhrhbdUsGEwP9T49lpw4KLmPNxTnRFaiH17VA7M0Q0UP3a82ic74svbmZgRrmGPW1teh+aF3VYgYCBI1nsK2jWava6ULXH7GBmrXBCFHBtWDJH2xxe6Xev94ssDeUcdVaNNQKwGjXYwMiFNHktJM2g38KpkZYt02snx4AI6l91rsxOpmH6f76kWGn8eI1fYH8p21edMZDJMkITj6Opb8KAXJgQso14GhdRYJGMRkvTO6dLqKKL0UQ== starlits@host1
</code>
  - id_rsa.pub 를 host2 에 .ssh/ 아래로 카피한다. <code>
starlits@host1:~/.ssh$ scp id_rsa.pub host2:.ssh/
</code>
  - host2에서 id_rsa.pub 를 authorized_keys 이름으로 변경한다. <code>
starlits@host2:~/.ssh$ ls
id_rsa.pub  known_hosts
starlits@host2:~/.ssh$ mv id_rsa.pub authorized_keys
starlits@host2:~/.ssh$ ls
authorized_keys  known_hosts
</code>
  - host1 에서 host2로 접근하면 암호를 물어보지 않는다.
  - host1 에서 host2로 명령을 직접 실행할 수도 있다. <code>
starlits@host1:~/.ssh$ ssh host2 PATH=/bin hostname
host2
</code>