title: cluster computing using starcluster and ipython on AWS
body: <p>I'm trying to experiment some with cluster computing on AWS. I'm completely new at this and having some issues. I'm trying to follow the tutorial found here: <a href="http://star.mit.edu/cluster/docs/latest/plugins/ipython.html#using-the-ipython-cluster" rel="noreferrer">http://star.mit.edu/cluster/docs/latest/plugins/ipython.html#using-the-ipython-cluster</a>. I use starcluster to start a cluster instance with the following:</p>
  
  <pre><code>starcluster start mycluster
  </code></pre>
  
  <p>Everything comes up as expected and it shows that the ipython plugin has loaded. I then try to execute the following command as shown in the tutorial:</p>
  
  <pre><code>starcluster sshmaster mycluster -u myuser
  </code></pre>
  
  <p>The connection fails, however, and tells me</p>
  
  <pre><code>Permission denied (publickey).
  </code></pre>
  
  <p>I am able to log in using</p>
  
  <pre><code>starcluster sshmaster mycluster
  </code></pre>
  
  <p>so I attempted to continue the tutorial logged in to the master but when I try to create the Client I receive and error:</p>
  
  <pre><code>AssertionError: Not a valid connection file or url: 
  u'/root/.ipython/profile_default/security/ipcontroller-client.json'
  </code></pre>
  
  <p>The only thing that I saw that seemed out of the ordinary is when the cluster was starting up this appeared:</p>
  
  <pre><code>&gt;&gt;&gt; Running plugin ipcluster
  &gt;&gt;&gt; Writing IPython cluster config files
  &gt;&gt;&gt; Starting IPython cluster with 7 engines
  &gt;&gt;&gt; Waiting for JSON connector file... 
  &gt;&gt;&gt; Creating IPCluster cache directory: /Users/username/.starcluster/ipcluster
  &gt;&gt;&gt; Saving JSON connector file to '/Users/username/.starcluster/ipcluster/mycluster-us-east-1.json'
  !!! ERROR - Error occurred while running plugin 'ipcluster':
  Traceback (most recent call last):
    File "/Library/Python/2.7/site-packages/StarCluster-0.93.3-py2.7.egg/starcluster/cluster.py", line 1506, in run_plugin
      func(*args)
    File "/Library/Python/2.7/site-packages/StarCluster-0.93.3-py2.7.egg/starcluster/plugins/ipcluster.py", line 276, in run
      plug.run(nodes, master, user, user_shell, volumes)
    File "&lt;string&gt;", line 2, in run
    File "/Library/Python/2.7/site-packages/StarCluster-0.93.3-py2.7.egg/starcluster/utils.py", line 87, in wrap_f
      res = func(*arg, **kargs)
    File "/Library/Python/2.7/site-packages/StarCluster-0.93.3-py2.7.egg/starcluster/plugins/ipcluster.py", line 228, in run
      cfile = self._start_cluster(master, n, profile_dir)
    File "/Library/Python/2.7/site-packages/StarCluster-0.93.3-py2.7.egg/starcluster/plugins/ipcluster.py", line 173, in _start_cluster
      master.ssh.get(json, local_json)
    File "/Library/Python/2.7/site-packages/StarCluster-0.93.3-py2.7.egg/starcluster/sshutils/__init__.py", line 431, in get
      self.scp.get(remotepaths, localpath, recursive=recursive)
    File "/Library/Python/2.7/site-packages/StarCluster-0.93.3-py2.7.egg/starcluster/sshutils/scp.py", line 141, in get
      self._recv_all()
    File "/Library/Python/2.7/site-packages/StarCluster-0.93.3-py2.7.egg/starcluster/sshutils/scp.py", line 242, in _recv_all
      msg = self.channel.recv(1024)
    File "build/bdist.macosx-10.8-intel/egg/ssh/channel.py", line 611, in recv
      raise socket.timeout()
  timeout
  </code></pre>
  
  <p>Any thoughts?</p>