Create an instance from an image using the CLI

How to create an instance from an image using the CLI

Follow the steps below to launch an instance from an image.

After you gather required parameters, run the following command to launch an instance. Specify the server name, flavor ID, and image ID.

$ nova boot --flavor FLAVOR_ID --image IMAGE_ID --key-name KEY_NAME \
  --user-data USER_DATA_FILE --security-groups SEC_GROUP_NAME --meta KEY=VALUE \
  INSTANCE_NAME

Optionally, you can provide a key name for access control and a security group for security. You can also include metadata key and value pairs. For example, you can add a description for your server by providing the –meta description=”My Server” parameter.

You can pass user data in a local file at instance launch by using the –user-data USER-DATA-FILE parameter.

Important: If you boot an instance with an INSTANCE_NAME greater than 63 characters, Compute truncates it automatically when turning it into a host name to ensure the correct work of dnsmasq. The corresponding warning is written into the nova-network.log file.

The following command launches the MyCirrosServer instance with the m1.small flavor (ID of 1), cirros-0.3.2-x86_64-uec image (ID of 397e713c-b95b-4186-ad46-6126863ea0a9), default security group, KeyPair01 key, and a user data file called cloudinit.file:

$ nova boot --flavor 1 --image 397e713c-b95b-4186-ad46-6126863ea0a9 \
  --security-groups default --key-name KeyPair01 --user-data cloudinit.file \
  myCirrosServer

Depending on the parameters that you provide, the command returns a list of server properties.

+-------------------------------------+-------------------------------------+
| Property                            | Value                               |
+-------------------------------------+-------------------------------------+
| OS-EXT-STS:task_state               | scheduling                          |
| image                               | cirros-0.3.2-x86_64-uec             |
| OS-EXT-STS:vm_state                 | building                            |
| OS-EXT-SRV-ATTR:instance_name       | instance-00000002                   |
| flavor                              | m1.small                            |
| id                                  | b3cdc6c0-85a7-4904-ae85-71918f734048|
| security_groups                     | [{u'name': u'default'}]             |
| user_id                             | 376744b5910b4b4da7d8e6cb483b06a8    |
| OS-DCF:diskConfig                   | MANUAL                              |
| accessIPv4                          |                                     |
| accessIPv6                          |                                     |
| progress                            | 0                                   |
| OS-EXT-STS:power_state              | 0                                   |
| OS-EXT-AZ:availability_zone         | nova                                |
| config_drive                        |                                     |
| status                              | BUILD                               |
| updated                             | 2013-07-16T16:25:34Z                |
| hostId                              |                                     |
| OS-EXT-SRV-ATTR:host                | None                                |
| key_name                            | KeyPair01                           |
| OS-EXT-SRV-ATTR:hypervisor_hostname | None                                |
| name                                | myCirrosServer                      |
| adminPass                           | tVs5pL8HcPGw                        |
| tenant_id                           | 66265572db174a7aa66eba661f58eb9e    |
| created                             | 2013-07-16T16:25:34Z                |
| metadata                            | {u'KEY': u'VALUE'}                  |
+-------------------------------------+-------------------------------------+

A status of BUILD indicates that the instance has started, but is not yet online.

A status of ACTIVE indicates that the instance is active.

Copy the server ID value from the id field in the output. Use the ID to get server details or to delete your server.
Copy the administrative password value from the adminPass field. Use the password to log in to your server.

Note: You can also place arbitrary local files into the instance file system at creation time by using the –file <dst-path=src-path> option. You can store up to five files. For example, if you have a special authorized keys file named special_authorized_keysfile that you want to put on the instance rather than using the regular SSH key injection, you can use the –file option as shown in the following example.
```
$ nova boot --image ubuntu-cloudimage --flavor 1 vm-name \
  --file /root/.ssh/authorized_keys=special_authorized_keysfile
```
Check if the instance is online.
```
$ nova list
```
The list shows the ID, name, status, and private (and if assigned, public) IP addresses for all instances in the project to which you belong:
```
+-------------+----------------------+--------+------------+-------------+------------------+
| ID          | Name                 | Status | Task State | Power State | Networks         |
+-------------+----------------------+--------+------------+-------------+------------------+
| 84c6e57d... | myCirrosServer       | ACTIVE | None       | Running     | private=10.0.0.3 |
| 8a99547e... | myInstanceFromVolume | ACTIVE | None       | Running     | private=10.0.0.4 |
+-------------+----------------------+--------+------------+-------------+------------------+
```
If the status for the instance is ACTIVE, the instance is online.
To view the available options for the nova list command, run the following command:
```
$ nova help list
```
Note: If you did not provide a key pair, security groups, or rules, you can access the instance only from inside the cloud through VNC. Even pinging the instance is not possible.

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