Chapter 6. Cloud Resources

This chapter discusses how to configure stacks and monitor cloud resources in RHEL OpenStack Platform.

6.1. Manage Stacks

The Orchestration service provides a framework through which you can define an instance's resource parameters (for example, floating IPs, volumes, or security groups) and properties (for example, key pairs, image to be used, or flavor) using Heat templates. These templates use a human-readable syntax and can be defined in text files (thereby allowing users to check them into version control). Templates allow you to easily deploy and re-configure infrastructure for applications within the OpenStack cloud.
Instances deployed using Heat templates through the Orchestration service are known as stacks. The dashboard allows you to launch, delete, and update stacks from Heat templates. You can input a Heat template directly into the dashboard, or use text files from your local file system or HTTP URL.

6.1.1. Download Sample Heat Templates

Red Hat Enterprise Linux OpenStack Platform includes sample templates you can use to test and study Heat's core functionality. To use these templates, install the openstack-heat-templates package: 
# yum install openstack-heat-templates
This package installs the sample Heat templates in /usr/share/openstack-heat-templates/software-config/example-templates.

6.1.2. Launch a Stack

  1. In the dashboard, select Project > Orchestration > Stacks, and click Launch Stack.
  2. Select an option from the Template Source list:
    Option Description
    File
    Use a local template file on your system. Select your file by clicking Template File > Browse.
    Direct Input
    Enter your template directly into the dashboard using the Template Data field.
    URL
    Use an external HTTP URL for the template. Specify the template's URL in the Template URL field.
    Note
    Red Hat Enterprise Linux OpenStack Platform includes sample templates. For more details, see Section 6.1.1, “Download Sample Heat Templates”.
  3. Select an option from the Environment Source list:
    Option Description
    File
    Use a .yaml file for the environment. Select your environment by clicking Environment File > Browse.
    Direct Input
    Enter your environment data directly into the dashboard using the Environment Data field.
  4. Click Next.
  5. Specify values for the following fields:
    Field Description
    Stack Name Name to identify the stack.
    Creation Timeout (minutes) Number of minutes before declaring a timeout on the stack launch.
    Rollback On Failure If selected, rolls back any changes or updates to the template if the stack launch fails.
    Password for user USERNAME Temporary password for the user launching the stack.
    The Launch Stack window may also contain other fields, depending on the parameters defined in the template. Update these fields as required.
  6. Click Launch.

6.1.3. Update a Stack

  1. If stack components need to be updated, edit your original template.
  2. In the dashboard, select Project > Orchestration > Stacks.
  3. Select the stack's Change Stack Template action.
  4. Select an option from the Template Source list:
    Option Description
    File
    Use a local template file on your system. Select your file by clicking Template File > Browse.
    Direct Input
    Enter your template directly into the dashboard using the Template Data field.
    URL
    Use an external HTTP URL for the template. Specify the template's URL in the Template URL field.
  5. Select an option from the Environment Source list:
    Option Description
    File
    Use a .yaml file for the environment. Select your environment by clicking Environment File > Browse.
    Direct Input
    Enter your environment data directly into the dashboard using the Environment Data field.
  6. Click Next.
  7. Specify values for the following fields:
    Field Description
    Creation Timeout (minutes) Number of minutes before declaring a timeout on the stack launch.
    Rollback On Failure If selected, rolls back any changes or updates to the template if the stack launch fails.
    Password for user USERNAME Temporary password for the user launching the stack.
    The Launch Stack window may also contain other fields, depending on the parameters defined in the template. Update these fields as required.
  8. Click Update. The Orchestration service re-launches the stack with the updated parameters. The Updated column on the Stacks table now reflects how long it has been since the stack was last updated.

6.1.4. Delete a Stack

You can delete a stack through the Stacks table:
  1. In the dashboard, select Project > Orchestration > Stacks.
  2. Select Delete Stack from the Actions column of a stack.
    Note
    Alternatively, you can delete multiple stacks simultaneously by selecting their respective checkboxes and clicking Delete Stacks.