多机免密互信

#设置一个空的私钥
ssh-keygen -f /root/.ssh/id_rsa -N ""
#id_rsa.pub变成authorized_keys
mv /root/.ssh/{id_rsa.pub,authorized_keys}
#将.ssh目录整个拷贝到其他主机
scp -r /root/.ssh IP:/root

免除询问yes/no

vim /etc/ssh/ssh_config

修改 StrictHostKeyChecking ask 为 StrictHostKeyChecking no，并取消注释