title: how to connect from one ec2 instance to another ec2 instance through ssh
body: <p>I have two amazon ec2 instances</p>
  
  <p>i can connect to those ec2 instance from my windows using putty (by the public key generated from the private key provided by amazon)</p>
  
  <p>now i want to install tungsten replicator into my ec2 instances
  and tungsten replicator needs ssh access from one ec2 instance to another ec2 instance</p>
  
  <p>i tried to check that ssh is working or not from one ec2 instance to another
  i tried:</p>
  
  <pre><code>ssh ec2-user@public ip of destination instance
  //also tried
  ssh ec2-user@private ip destination instance
  </code></pre>
  
  <p>but its not working</p>
  
  <p>i got following error:</p>
  
  <pre><code>Permission denied (publickey,gssapi-keyex,gssapi-with-mic)
  </code></pre>
  
  <p>i have search on google and tried some trick but none of them worked </p>
  
  <p>sometime i got following error:</p>
  
  <pre><code>Address public_ip maps to xxxx.eu-west-1.compute.amazonaws.com, but this does not map back to the address - POSSIBLE BREAK-IN ATTEMPT!
  </code></pre>
  
  <p>can anyone please tell me how to connect ssh from one ec2 instance to another</p>