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Hello,

In my essex install on RHEL6, there is a problem with the metadata service.
The metadata service works for instances running on the controller node, 
where
the nova-api(metadata service) is running. But for the other worker nodes,
the metadata service is intermittent, ie. the instances sometimes can 
get its metadata,
sometime it fails with errors like:

$> curl -v http://169.254.169.254:8775/
* About to connect() to 169.254.169.254 port 8775 (#0)
*   Trying 169.254.169.254... Connection timed out
* couldn't connect to host
* Closing connection #0
curl: (7) couldn't connect to host

Any idea where should I start investigating this?

Thanks,
Xin