1. First check whether the SSH package has been installed in linux, and use rpm-QA | grepsash.

2. Confirm that the ssh service has been started. Take centos system as an example.

3. The path to find the SSh service configuration file is usually the file sshd_config in the /etc/ssh directory.

Note: SSH port defaults to 22. If you want to modify, edit port 22 directly. Please note that the preceding "#" should be deleted, then saved and restarted.