# OpenStack nova API start error OpenStack-nova-api doesn't start, this error is from the services boot priority in many times. ``` $ service openstack-nova-api start 2015-03-03 15:05:06.402 3313 ERROR nova.wsgi [-] Could not bind to 0.0.0.0:8775 2015-03-03 15:05:06.402 3313 CRITICAL nova [-] error: [Errno 98] Address already in use $ service openstack-nova-api status openstack-nova-api dead but pid file exists\* ``` This Error happens because openstack-nova-api and openstack-nova-metadata-api use the same ports. You can start nova-api stopping metadata-api service and starting nova-api before, then start again metadata-api service. ``` $ service openstack-nova-metadata-api stop $ service openstack-nova-api start $ service openstack-nova-metadata-api ``` This should fix your issue. After this you can set up boot order to this processes ``` update-rc.d openstack-nova-api defaults [order] ``` Example: If openstack-nova-metadata-api got an order boot of S90 openstack-nova-metadata-api, you should use update-rc to set nova-api start before nova-metadata-api ``` update-rc.d openstack-nova-api defaults 90 ``` This will set the priority of nova-api with the priority of nova-metadata-api, wich means that nova-api will run before metadata-api. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://blog.egonzalez.org/openstack/index/openstack-nova-api-start-error.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.