Red Hat Summit25장. Configuring the OpenSSH server and client by using RHEL system roles
You can use the sshd RHEL system role to configure OpenSSH servers and the ssh RHEL system role to configure OpenSSH clients consistently, in an automated fashion, and on any number of RHEL systems at the same time.
Such configurations are necessary for any system where secure remote interaction is needed, for example:
- Remote system administration: securely connecting to your machine from another computer by using an SSH client.
- Secure file transfers: the Secure File Transfer Protocol (SFTP) provided by OpenSSH securely transfers files between your local machine and a remote system.
- Automated DevOps pipelines: automating software deployments that require secure connection to remote servers (CI/CD pipelines).
- Tunneling and port forwarding: forwarding a local port to access a web service on a remote server behind a firewall. For example a remote database or a development server.
- Key-based authentication: more secure alternative to password-based logins.
- Certificate-based authentication: centralized trust management and better scalability.
- Enhanced security: disabling root logins, restricting user access, enforcing strong encryption and other such forms of hardening ensures stronger system security.
25.1. How the sshd RHEL system role maps settings from a playbook to the configuration file
In the sshd RHEL system role playbook, you can define the parameters for the server SSH configuration file. If you do not specify these settings, the role produces the sshd_config file that matches the RHEL defaults.
In all cases, booleans correctly render as yes and no in the final configuration on your managed nodes. You can use lists to define multi-line configuration items. For example:
sshd_ListenAddress:
- 0.0.0.0
- '::'renders as:
ListenAddress 0.0.0.0
ListenAddress ::
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