Define a new role¶

You must define a new role in node_roles.yaml.

The automatically generated plugin contains one example role in the file, but you can delete the contents of the file and start with a new role:

fuel-plugin-example_role:
  name: Example plugin role
  description: Just a test role
  weight: 1000

The only required field besides the ID here is name, but this is always a good idea to provide some description of the role’s purpose. The parameter weight defines relative placement of the role in the list of roles in the Fuel web UI. Standard roles have weights from 10 to 100, with the weight 1000 your role will appear at the end of the list. You can look up the exact values as well as the definitions for the standard roles at openstack.yaml on GitHub .

Like plugin tasks and unlike plugin settings, role definitions are affected by the fuel --sync` command and can be easily updated.

To verify that your new role is defined and can be assigned to new nodes use the button Add nodes in the Nodes UI tab: url http://<fuel ip>:8000/#cluster/<cluster id>/nodes/add.

You must define a new group for the tasks that belong to the new role in deployment_tasks.yaml:

- id: fuel-plugin-example_role
  type: group
  role: [fuel-plugin-example_role]
  tasks: [globals]
  parameters:
   strategy:
    type: parallel

The ID of the group must be the same as the ID of the new role. You define the list of the core tasks, which run on the new role, in the field tasks. The parameter strategy is required and it defines how the deployment should proceed if there are multiple nodes to be deployed with the role.

The possible values for strategy are:

• one-by-one – all the nodes with the role will be deployed

  sequentially, one after another

• parallel – nodes will be deployed in parallel, at the same time

The next step after determining core tasks that should be run on your role, will be to define plugin tasks and the process is the same as the one that described in Actions for existing roles. The only difference is that you will use the ID of the new role in the task definition:

- id: fuel-plugin-example-iotop
  type: puppet
  role: [fuel-plugin-example_role]
  requires: [post_deployment_start]
  required_for: [post_deployment_end]
  parameters:
   puppet_manifest: puppet/manifests/install_iotop.pp
   puppet_modules: puppet/modules:/etc/puppet/modules

The difference between the deployment of the nodes with the new role and the pre-existing ones is that only the core tasks that you explicitly defined in the tasks field of the role’s group definition will run on the node with the new role, while there is a predefined list of core tasks to run on the nodes with pre-existing roles.

# fuel env create --name test-plugin-role-1 --rel 2
Environment 'test-plugin-role-1' with id=3 was created!
# id=`fuel env | grep test-plugin-role-1 | tr -d  ' ' \
  |cut -d\| -f1`
# fuel --env $id settings download
# awk -F: 'BEGIN {OFS = FS} $1 ~ "fuel-plugin-example" \
  { f=1 } f && $1 ~ "enabled" { f=0; $2=" true"} \
  { print } ' settings_${id}.yaml > tmp && mv \
  tmp settings_${id}.yaml
# fuel --env $id settings upload
# fuel --env $id node set --node 10 --role
  fuel-plugin-example_role
Nodes [10] with roles ['fuel-plugin-example_role'] were added
to environment 3
# fuel --env $id deploy-changes