Secure SHell
Tweak
키 생성 및 복사
ssh-keygen [root@host ~]# ssh-copy-id node1.ssh/confg
$ vim ~/.ssh/config host node1 node1.group node1.group.domain.com
hostname node1.group.domain.com
user root
ForwardX11 yes
$ chmod 0600 ~/.ssh/configDNS 미사용
vim /etc/ssh/sshd_config useDNS no