title: Cannot ssh into EC2 instance anymore: Permission denied (publickey,gssapi-keyex,gssapi-with-mic)
body: <p>I was using ssh client from mac to log into the EC2 instance and it was working fine:</p>
  
  <pre><code>ssh -i "key.pem" centos@10.193.80.253
  </code></pre>
  
  <p>I have started getting issues after I tried configuring ssh for git in the EC2 which introduced following changes:</p>
  
  <ol>
  <li><p>Added config file in ~/.ssh with the following content</p>
  
  <p><code>Host *
   AddKeysToAgent yes
   UseKeychain yes
   IdentityFile ~/.ssh/id_rsa</code></p></li>
  <li>I added the id_rsa into into ~/.ssh prior to step 1</li>
  </ol>
  
  <p>I am not sure if these changes are causing any issues.</p>