# Placement directive In Juju, a **placement directive** is an option based on the `--to` flag that can be passed to certain commands to specify a deploy location, where the commands include [juju add-machine](https://documentation.ubuntu.com/juju/2.9/reference/juju-cli/list-of-juju-cli-commands/add-machine.md#command-juju-add-machine) , [juju add-unit](https://documentation.ubuntu.com/juju/2.9/reference/juju-cli/list-of-juju-cli-commands/add-unit.md#command-juju-add-unit), [juju bootstrap](https://documentation.ubuntu.com/juju/2.9/reference/juju-cli/list-of-juju-cli-commands/bootstrap.md#command-juju-bootstrap), [juju deploy](https://documentation.ubuntu.com/juju/2.9/reference/juju-cli/list-of-juju-cli-commands/deploy.md#command-juju-deploy), [juju enable-ha](https://documentation.ubuntu.com/juju/2.9/reference/juju-cli/list-of-juju-cli-commands/enable-ha.md#command-juju-enable-ha), and the location is (1) an existing or a new machine or (2) a key-value pair specifying a subnet, system ID, or an availability zone. Example: `juju add-machine --to 1`, `juju deploy --to zone=us-east-1a` The rest of this document gives details about the locations. #### CAUTION When the location is a key-value pair, its availability and meaning may vary from cloud to cloud. For details see [List of supported clouds](https://documentation.ubuntu.com/juju/2.9/reference/cloud/list-of-supported-clouds.md#list-of-supported-clouds) > ``. ## List of placement directive locations ### `` Depending on whether this is an existing machine or a new machine, this will be: - The existing machine ID. **Examples:** `1` (existing machine `1`), `5/lxd/0` (existing container `0` on machine `5`) - A new machine, specifying a type or relative location. **Examples:** `lxd` (new container on a new machine), `lxd:5` (new container on machine 5) > See more: [Machine designations](https://documentation.ubuntu.com/juju/2.9/reference/machine.md#machine-designations) ### `subnet=` Available for Azure and AWS EC2. ### `system-id=` Available for MAAS. ### `zone=` **Purpose:** To specify an availability zone. #### IMPORTANT The `zone` placement directive may be used to override a `zones` [constraint](https://documentation.ubuntu.com/juju/2.9/reference/constraint.md#constraint). **Example:** `zone=us-east-1a`