"execution_count" error when running a job on a remote IPython cluster
Question: I am running an IPython cluster (SSH) on a remote Linux machine, and I am
using Mac OS X with IPython to use that cluster. In IPython on Mac I write:

    
    
    from IPython.parallel import Client
    c = Client('~/ipcontroller-client.json', sshserver="me@remote_linux_machine")
    dview=c[:]
    dview.scatter('m', arange(100))
    

where `'~/ipcontroller-client.json'` is the file copied from
`remote_linux_machine`. Everything works up to this point.

When I try to use parallel magic `%px` I get an error:

    
    
    /opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/IPython/parallel/client/client.pyc
    in __init__(self, msg_id, content, metadata)
         80         self.msg_id = msg_id
         81         self._content = content
    ---> 82         self.execution_count = content['execution_count']
         83         self.metadata = metadata
         84 
    
    KeyError: 'execution_count'
    

Same idea, but when I run the cluster on _localhost_ it works perfectly.

Should parallel magic work at all for remote SSH cluster case?


Answer: The problem is now fixed: one needs to make sure the IPython versions are the
same (mine are 0.13.2) on the cluster and on the machine you are using it.

On the Linux machine I had to specify the version I needed to install as the
standard IPython was installed with version 0.12.1:

    
    
    sudo apt-get install ipython=0.13.2-1~ubuntu12.04.1
    

