How to control remote hosts and execute commands remotely through ssh

It is very simple and practical to teach you how to control the remote host through ssh and how to remotely execute commands on the remote host through ssh. Step 1: Set ssh authentication-free. authentication-free means that you can directly log on without password authentication, which is particularly useful when writing script server control. Every two steps teach you how to control the remote host through ssh, and how to remotely execute commands through ssh to control remote host remote command execution in two steps, which is very simple and practical. Step 1: Set ssh authentication-free. authentication-free means that you can directly log on without password authentication, which is particularly useful when writing script server control. Every two steps is to execute commands on the remote server. suppose there are two servers, one is SA and the other is SB. Now I want to control SB on SA. Format: ssh SB _ username @ SB_IP "command" for example: ssh tuxedo@172.16.18.54 "echo aaa> hzs_test.txt" ssh tuxedo@172.16.18.54 'echo-e "haha \ n hoho"> hzs_test.txt'