How to change the resource limits of a DreamCompute instance

Overview

To change the resource limits (vCPU/RAM) of a specific instance, you need to change its 'Flavor'. This can be done within the DreamCompute dashboard, or using the OpenStack CLI. Use whichever option you're more comfortable with.

Changing resource limits in the dashboard

  1. Navigate to the DreamCompute page.
  2. Click the View Dashboard button.
  3. In the left menu, click Compute.
  4. From the dropdown, click Instances.
  5. To the right of your instance, click the Create Snapshot dropdown.
  6. From the menu, select Resize Instance.
  7. In the pop-up, select the New Flavor you want from the dropdown, then click the Resize button.

    After a few moments, the instance will report that it is in a Resize/Migrate status and ask you to "Confirm or Revert Resize/Migrate".

  8. Click the Confirm Resize/Migrate button under the Actions column.

You can also cancel the resize by clicking the dropdown arrow and selecting the Revert Resize/Migrate action.

After confirming or reverting the resize/migrate, the instance status will switch back to Active.

Changing the resource limit using the OpenStackCLI

To run the commands below, make sure you have installed the OpenStack command line client.

In the following examples, myInstance is the name of your instance. You can view the name of your instance in the DreamCompute dashboard.

  1. Run the following command to display information about an instance. This includes its size, which is shown as the value of the flavor property.
    [user@localhost]$ openstack server show myInstance
    +-----------------------------+--------------------------------------------------------------+
    | Field                       | Value                                                        |
    +-----------------------------+--------------------------------------------------------------+
    | OS-DCF:diskConfig           | AUTO                                                         |
    | OS-EXT-AZ:availability_zone | iad-2                                                        |
    | OS-EXT-STS:power_state      | Running                                                      |
    | OS-EXT-STS:task_state       | None                                                         |
    | OS-EXT-STS:vm_state         | active                                                       |
    | OS-SRV-USG:launched_at      | 2017-10-06T01:23:41.000000                                   |
    | OS-SRV-USG:terminated_at    | None                                                         |
    | accessIPv4                  |                                                              |
    | accessIPv6                  |                                                              |
    | config_drive                | True                                                         |
    | created                     | 2017-10-06T01:23:12Z                                         |
    | flavor                      | gp1.subsonic (100)                                           |
    | hostId                      | 9d915ea664129303798621bb83cb3b2ac04c445cae6fc9e58e90b5d6     |
    | id                          | 246e50c8-22fa-4310-b972-a71cd0df43bf                         |
    | image                       |                                                              |
    | key_name                    | myKey                                                        |
    | name                        | myInstance                                                   |
    | progress                    | 0                                                            |
    | project_id                  | e52edb2a460548zf950ba86497300079                             |
    | properties                  |                                                              |
    | security_groups             | name='default'                                               |
    | status                      | ACTIVE                                                       |
    | updated                     | 2017-10-06T01:23:41Z                                         |
    | user_id                     | 29815515c3be4d49a27e787a63eb8320                             |
    | volumes_attached            | id='e6b7qecc-8be2-4199-a4ad-9905b5591fed'                    |
    +-----------------------------+--------------------------------------------------------------+
    

    In this example, the size (flavor) of the instance is gp1.subsonic (100).

  2. List the available flavors with the following command.
    [user@localhost]$ openstack flavor list
    +-----+----------------+-------+------+-----------+-------+-----------+
    | ID  | Name           |   RAM | Disk | Ephemeral | VCPUs | Is Public |
    +-----+----------------+-------+------+-----------+-------+-----------+
    | 100 | gp1.subsonic   |  1024 |   80 |         0 |     1 | True      |
    | 200 | gp1.supersonic |  2048 |   80 |         0 |     1 | True      |
    | 300 | gp1.lightspeed |  4096 |   80 |         0 |     2 | True      |
    | 400 | gp1.warpspeed  |  8192 |   80 |         0 |     4 | True      |
    | 50  | gp1.semisonic  |   512 |   80 |         0 |     1 | True      |
    | 500 | gp1.hyperspeed | 16384 |   80 |         0 |     8 | True      |
    +-----+----------------+-------+------+-----------+-------+-----------+
    
  3. Resize the instance using the openstack server resize command while specifying the new flavor and instance name.

    You can also include the –-wait parameter to display the resize progress.

    [user@localhost]$ openstack server resize --flavor 200 --wait myInstance
    Complete
    

    By default, the openstack server resize command gives the guest operating system 60 seconds to perform a controlled shutdown before the instance is powered off and the instance is resized.

    The timeout value can be overridden on a per image basis by means of os_shutdown_timeout that is an image metadata setting allowing different types of operating systems to specify how much time they need to shut down cleanly.

  4. Display the status for the instance using the following command.
    [user@localhost]$ openstack server show myInstance -c status
    +--------+----------------+
    | Field | Value |
    +--------+----------------+
    | status | VERIFY_RESIZE |
    +--------+----------------+

    When the resize completes, the status becomes VERIFY_RESIZE.

  5. Confirm the resize with --confirm.
    [user@localhost]$ openstack server resize --confirm myInstance
  6. Run openstack server show myInstance -c status again and you'll see the status is now ACTIVE.

    Revert the resize if it fails or does not work as expected. For example:

    [user@localhost]$ openstack server resize --revert myInstance

    The instance status becomes ACTIVE.

Did this article answer your questions?

Article last updated PST.

Still not finding what you're looking for?