def collect(self, device, unused):

        client = NovaAPIClient(
            device.zCommandUsername,
            device.zCommandPassword,
            device.zOpenStackAuthUrl,
            device.zOpenStackProjectId,
            device.zOpenStackRegionName,
        )

        keystone_client = KeystoneAPIClient(
            device.zCommandUsername,
            device.zCommandPassword,
            device.zOpenStackAuthUrl,
            device.zOpenStackProjectId,
            admin=True,
        )

        results = {}

        results["tenants"] = []
        try:
            result = yield keystone_client.tenants()
            results["tenants"] = result["tenants"]
            log.debug("tenants: %s\n" % str(results["tenants"]))

        except (ConnectError, TimeoutError), e:
            log.error(self._keystonev2errmsg, e)