Select hosts where instances are launched¶

With the appropriate permissions, you can select which host instances are launched on and which roles can boot instances on this host.

1. To select the host where instances are launched, use the --availability-zone ZONE:HOST:NODE parameter on the openstack server create command.

   For example:

   $ openstack server create --image IMAGE --flavor m1.tiny \
     --key-name KEY --availability-zone ZONE:HOST:NODE \
     --nic net-id=UUID SERVER
   

   Note

   HOST and NODE are optional parameters. In such cases, use the --availability-zone ZONE::NODE, --availability-zone ZONE:HOST or --availability-zone ZONE.

2. To specify which roles can launch an instance on a specified host, enable the create:forced_host option in the policy.json file. By default, this option is enabled for only the admin role. If you see Forbidden (HTTP 403) in return, then you are not using admin credentials.

3. To view the list of valid zones, use the openstack availability zone list command.

   $ openstack availability zone list
   +-----------+-------------+
   | Zone Name | Zone Status |
   +-----------+-------------+
   | zone1     | available   |
   | zone2     | available   |
   +-----------+-------------+
   

4. To view the list of valid compute hosts, use the openstack host list command.

   $ openstack host list
   +----------------+-------------+----------+
   | Host Name      | Service     | Zone     |
   +----------------+-------------+----------+
   | compute01      | compute     | nova     |
   | compute02      | compute     | nova     |
   +----------------+-------------+----------+
   

5. To view the list of valid compute nodes, use the openstack hypervisor list command.

   $ openstack hypervisor list
   +----+---------------------+
   | ID | Hypervisor Hostname |
   +----+---------------------+
   |  1 | server2             |
   |  2 | server3             |
   |  3 | server4             |
   +----+---------------------+