Open Stack

Hi guys
	I recently play around with 'x-openstack-request-id' header but have a dump question about how it works. At beginning, I thought an action across different services should use a same request-id but it looks like this is not the true. 

First I read the spec: https://blueprints.launchpad.net/nova/+spec/cross-service-request-id which said "This ID and the request ID of the other service will be logged at service boundaries". and I see cinder/neutron/glance will attach its context's request-id as the value of "x-openstack-request-id" header to its response while nova use X-Compute-Request-Id. This is easy to understand. So It looks like each service should generate its own request-id and attach to its response, that's all.

But then I see glance read 'X-Openstack-Request-ID' to generate the request-id while cinder/neutron/nova read 'openstack.request_id' when using with keystone. It is try to reuse the request-id from keystone.

This totally confused me. It would be great if you can correct me or point me some reference. Thanks a lot

Best Regards,

Tan