Select a specific host to boot instances on
If you have the appropriate permissions, you can select the specific host where the
instance will be launched. This is done using the --availability_zone
zone:host
arguments to the nova boot command. For example:
$ nova boot --image <uuid> --flavor m1.tiny --key_name test --availability-zone nova:server2
Starting with the Grizzly release, you can specify which roles are permitted to boot
an instance to a specific host with the create:forced_host setting
within policy.json on the desired roles. By default, only the admin
role has this setting enabled.
You can view the list of valid compute hosts by using the nova
hypervisor-list command, for
example:$ nova hypervisor-list
+----+---------------------+
| ID | Hypervisor hostname |
+----+---------------------+
| 1 | server2 |
| 2 | server3 |
| 3 | server4 |
+----+---------------------+
The --availability_zone
zone:host
flag replaced the --force_hosts scheduler hint for specifying a
specific host, starting with the Folsom release.