title: Fail to git clone, push, pull with ssh, raise kex_exchange_identification error
body: <p>On macOS Catalina, when I push my local repo by </p>
  
  <pre><code>&gt; git push origin master
  kex_exchange_identification: Connection closed by remote host
  fatal: Could not read from remote repository.
  
  Please make sure you have the correct access rights
  and the repository exists.
  </code></pre>
  
  <p>And I try ssh to git@github.com also, it returns</p>
  
  <pre><code>&gt; ssh -Tv git@github.com
  OpenSSH_8.1p1, LibreSSL 2.7.3
  debug1: Reading configuration data /Users/user/.ssh/config
  debug1: /Users/user/.ssh/config line 1: Applying options for *
  debug1: Reading configuration data /etc/ssh/ssh_config
  debug1: /etc/ssh/ssh_config line 47: Applying options for *
  debug1: Connecting to github.com port 22.
  debug1: Connection established.
  debug1: identity file /Users/user/.ssh/id_rsa type 0
  debug1: identity file /Users/user/.ssh/id_rsa-cert type -1
  debug1: Local version string SSH-2.0-OpenSSH_8.1
  kex_exchange_identification: Connection closed by remote host
  </code></pre>
  
  <p>my config file is</p>
  
  <pre><code>Host *                                                                                                                                                                                                  
      AddKeysToAgent yes 
      UseKeychain yes 
      IdentityFile ~/.ssh/id_rsa
      ForwardX11 yes 
  Host 23
      HostName 10.214.130.23
      User ****
  Host 26
      HostName 10.214.130.26
      User ****
  Host 27
      HostName 10.214.130.27
      User ****
  Host desktop
      HostName 10.214.130.251
      User ****
  </code></pre>
  
  <p>At the beginning, I think the id_rsa maybe wrong, so I use the same key <code>~/.ssh/id_rsa</code> on the other Linux server, it works correctly.</p>
  
  <pre><code>&gt; ssh -T git@github.com
  Hi weleen! You've successfully authenticated, but GitHub does not provide shell access.
  </code></pre>
  
  <p>I find some similar questions but not solved.</p>