Setting in /etc/nova/nova.conf

[cells]
name = region
cell_type = api
enable = True


When API call to get cells -

curl -i 'http://10.0.9.40:8774/v2/dcab4e3fc2734bad97c43d46bb77d076/os-cells' -X GET -H "X-Auth-Project-Id: demo" -H "User-Agent: python-novaclient" -H "Accept: application/json" -H "X-Auth-Token:<token>"
HTTP/1.1 200 OK
Content-Type: application/json
Content-Length: 111
X-Compute-Request-Id: req-e83c337a-a7d9-47e5-a472-72cd41126f21
Date: Thu, 24 Apr 2014 04:12:34 GMT

{"cells": [{"username": "guest", "rpc_host": "10.0.9.40", "type": "child", "name": "child", "rpc_port": 5672}]}



During particular cell show (using cell name as "child")-

curl -i 'http://10.0.9.40:8774/v2/dcab4e3fc2734bad97c43d46bb77d076/os-cells/child' -X GET -H "X-Auth-Project-Id: demo" -H "User-Agent: python-novaclient" -H "Accept: application/json" -H "X-Auth-Token: <token>"

HTTP/1.1 500 Internal Server Error
Content-Length: 128
Content-Type: application/json; charset=UTF-8
X-Compute-Request-Id: req-ba2503bd-3948-4cce-8ee6-543aa597497b
Date: Thu, 24 Apr 2014 04:10:33 GMT

{"computeFault": {"message": "The server has either erred or is incapable of performing the requested operation.", "code": 500}}

Note: when using cell name as "api"/"region" 404 is returned.