Mac OS

SSH（Secure Shell）是一种通用的、功能强大的、基于软件的网络安全解决方案。计算机每次向网络发送数据时，SSH都会自动对其进行加密。运行 OS X 又或者是 macOS 的较新 Mac 设备都会默认预装 SSH，不过 SSH 守护进程是默认禁用的。今天我们就来一起学习如何通过终端指令来开启和关闭 SSH。

通过终端查看 SSH 远程登录是否已经开启

想要查看 Mac 上 SSH 的当前状态？使用简单的终端就可以检查 SSH 和远程登录目前是否已经开启：

1
sudo systemsetup -getremotelogin

如果已经开启的话，指令会显示 “Remote Login: On” ，反之就会显示“Remote Login: Off”。

通过终端指令开启Mac的SSH

要快速开启 SSH 服务器并允许 SSH 连接进入当前 Mac，使用下列指令：

1
sudo systemsetup -setremotelogin on

输入指令后并没有任何确认信息表明远程登录和 SSH 已经开启，但你可以使用上文提到的方法来检查是否开启成功。

通过终端指令关闭Mac的SSH

如果你想通过终端指令禁用 SSH 服务器并阻止远程连接，输入下列指令：

1
sudo systemsetup -setremotelogin off

Windows

Testing your SSH connection:

After you’ve set up your SSH key and added it to your GitHub account, you can test your connection.

  1. Open Git Bash.
  2. Enter the following: 
    1
    2
    $ ssh -T git@github.com
    # Attempts to ssh to GitHub
    You may see a warning like this: 
    1
    2
    3
    > The authenticity of host 'github.com (IP ADDRESS)' can't be established.
    > RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48.
    > Are you sure you want to continue connecting (yes/no)?
    or like this: 
    1
    2
    3
    > The authenticity of host 'github.com (IP ADDRESS)' can't be established.
    > RSA key fingerprint is SHA256:nThbg6kXUpJWGl7E1IGOCspRomTxdCARLviKw6E5SY8.
    > Are you sure you want to continue connecting (yes/no)?
  3. Verify that the fingerprint in the message you see matches one of the messages in step 2, then type yes: 
    1
    2
    > Hi username! You've successfully authenticated, but GitHub does not
    > provide shell access.
  4. Verify that the resulting message contains your username. If you receive a “permission denied” message, see “Error: Permission denied (publickey)“.

reference