Chapter 4. Configuration Hooks

The director provides a mechanism to perform configuration on all nodes upon the initial creation of the Overcloud. The director achieves this through cloud-init, which you can call using the OS::TripleO::NodeUserData resource type.

In this example, you will update the nameserver with a custom IP address on all nodes. You must first create a basic heat template (/home/stack/templates/nameserver.yaml) that runs a script to append each node’s resolv.conf with a specific nameserver. You can use the OS::TripleO::MultipartMime resource type to send the configuration script.

heat_template_version: 2014-10-16

description: >
  Extra hostname configuration

resources:
  userdata:
    type: OS::Heat::MultipartMime
    properties:
      parts:
      - config: {get_resource: nameserver_config}

  nameserver_config:
    type: OS::Heat::SoftwareConfig
    properties:
      config: |
        #!/bin/bash
        echo "nameserver 192.168.1.1" >> /etc/resolv.conf

outputs:
  OS::stack_id:
    value: {get_resource: userdata}

Next, create an environment file (/home/stack/templates/firstboot.yaml) that registers your heat template as the OS::TripleO::NodeUserData resource type.

resource_registry:
  OS::TripleO::NodeUserData: /home/stack/templates/nameserver.yaml

To add the first boot configuration, add the environment file to the stack along with your other environment files when first creating the Overcloud. For example:

$ openstack overcloud deploy --templates \
    ...
    -e /home/stack/templates/firstboot.yaml \
    ...

The -e applies the environment file to the Overcloud stack.

This adds the configuration to all nodes when they are first created and boot for the first time. Subsequent inclusions of these templates, such as updating the Overcloud stack, does not run these scripts.

The Overcloud uses Puppet for the core configuration of OpenStack components. The director provides a set of hooks to provide custom configuration for specific node roles after the first boot completes and before the core configuration begins. These hooks include:

In this example, you first create a basic heat template (/home/stack/templates/nameserver.yaml) that runs a script to write to a node’s resolv.conf with a variable nameserver.

heat_template_version: 2014-10-16

description: >
  Extra hostname configuration

parameters:
  server:
    type: string
  nameserver_ip:
    type: string
  DeployIdentifier:
    type: string

resources:
  CustomExtraConfigPre:
    type: OS::Heat::SoftwareConfig
    properties:
      group: script
      config:
        str_replace:
          template: |
            #!/bin/sh
            echo "nameserver _NAMESERVER_IP_" > /etc/resolv.conf
          params:
            _NAMESERVER_IP_: {get_param: nameserver_ip}

  CustomExtraDeploymentPre:
    type: OS::Heat::SoftwareDeployment
    properties:
      server: {get_param: server}
      config: {get_resource: CustomExtraConfigPre}
      actions: ['CREATE','UPDATE']
      input_values:
        deploy_identifier: {get_param: DeployIdentifier}

outputs:
  deploy_stdout:
    description: Deployment reference, used to trigger pre-deploy on changes
    value: {get_attr: [CustomExtraDeploymentPre, deploy_stdout]}

In this example, the resources section contains the following:

Next, create an environment file (/home/stack/templates/pre_config.yaml) that registers your heat template to the role-based resource type. For example, to apply only to Controller nodes, use the ControllerExtraConfigPre hook:

resource_registry:
  OS::TripleO::ControllerExtraConfigPre: /home/stack/templates/nameserver.yaml

parameter_defaults:
  nameserver_ip: 192.168.1.1

To apply the configuration, add the environment file to the stack along with your other environment files when creating or updating the Overcloud. For example:

$ openstack overcloud deploy --templates \
    ...
    -e /home/stack/templates/pre_config.yaml \
    ...

This applies the configuration to all Controller nodes before the core configuration begins on either the initial Overcloud creation or subsequent updates.

The Overcloud uses Puppet for the core configuration of OpenStack components. The director provides a hook to configure all node types after the first boot completes and before the core configuration begins:

In this example, you first create a basic heat template (/home/stack/templates/nameserver.yaml) that runs a script to append each node’s resolv.conf with a variable nameserver.

heat_template_version: 2014-10-16

description: >
  Extra hostname configuration

parameters:
  server:
    type: string
  nameserver_ip:
    type: string
  DeployIdentifier:
    type: string

resources:
  CustomExtraConfigPre:
    type: OS::Heat::SoftwareConfig
    properties:
      group: script
      config:
        str_replace:
          template: |
            #!/bin/sh
            echo "nameserver _NAMESERVER_IP_" >> /etc/resolv.conf
          params:
            _NAMESERVER_IP_: {get_param: nameserver_ip}

  CustomExtraDeploymentPre:
    type: OS::Heat::SoftwareDeployment
    properties:
      server: {get_param: server}
      config: {get_resource: CustomExtraConfigPre}
      actions: ['CREATE','UPDATE']
      input_values:
        deploy_identifier: {get_param: DeployIdentifier}

outputs:
  deploy_stdout:
    description: Deployment reference, used to trigger pre-deploy on changes
    value: {get_attr: [CustomExtraDeploymentPre, deploy_stdout]}

In this example, the resources section contains the following:

Next, create an environment file (/home/stack/templates/pre_config.yaml) that registers your heat template as the OS::TripleO::NodeExtraConfig resource type.

resource_registry:
  OS::TripleO::NodeExtraConfig: /home/stack/templates/nameserver.yaml

parameter_defaults:
  nameserver_ip: 192.168.1.1

To apply the configuration, add the environment file to the stack along with your other environment files when creating or updating the Overcloud. For example:

$ openstack overcloud deploy --templates \
    ...
    -e /home/stack/templates/pre_config.yaml \
    ...

This applies the configuration to all nodes before the core configuration begins on either the initial Overcloud creation or subsequent updates.

A situation might occur where you have completed the creation of your Overcloud but want to add additional configuration to all roles, either on initial creation or on a subsequent update of the Overcloud. In this case, you use the following post-configuration hook:

In this example, you first create a basic heat template (/home/stack/templates/nameserver.yaml) that runs a script to append each node’s resolv.conf with a variable nameserver.

heat_template_version: 2014-10-16

description: >
  Extra hostname configuration

parameters:
  servers:
    type: json
  nameserver_ip:
    type: string
  DeployIdentifier:
    type: string

resources:
  CustomExtraConfig:
    type: OS::Heat::SoftwareConfig
    properties:
      group: script
      config:
        str_replace:
          template: |
            #!/bin/sh
            echo "nameserver _NAMESERVER_IP_" >> /etc/resolv.conf
          params:
            _NAMESERVER_IP_: {get_param: nameserver_ip}

  CustomExtraDeployments:
    type: OS::Heat::SoftwareDeploymentGroup
    properties:
      servers:  {get_param: servers}
      config: {get_resource: CustomExtraConfig}
      actions: ['CREATE','UPDATE']
      input_values:
        deploy_identifier: {get_param: DeployIdentifier}

In this example, the resources section contains the following:

Next, create an environment file (/home/stack/templates/post_config.yaml) that registers your heat template as the OS::TripleO::NodeExtraConfigPost: resource type.

resource_registry:
  OS::TripleO::NodeExtraConfigPost: /home/stack/templates/nameserver.yaml

parameter_defaults:
  nameserver_ip: 192.168.1.1

To apply the configuration, add the environment file to the stack along with your other environment files when creating or updating the Overcloud. For example:

$ openstack overcloud deploy --templates \
    ...
    -e /home/stack/templates/post_config.yaml \
    ...

This applies the configuration to all nodes after the core configuration completes on either initial Overcloud creation or subsequent updates.

The Heat template collection contains a set of parameters to pass extra configuration to certain node types. These parameters save the configuration as hieradata for the node’s Puppet configuration. These parameters are:

To add extra configuration to the post-deployment configuration process, create an environment file that contains these parameters in the parameter_defaults section. For example, to increase the reserved memory for Compute hosts to 1024 MB and set the VNC keymap to Japanese:

parameter_defaults:
  NovaComputeExtraConfig:
    nova::compute::reserved_host_memory: 1024
    nova::compute::vnc_keymap: ja

Include this environment file when running openstack overcloud deploy.

You can set Puppet hieradata for individual nodes using the Heat template collection. To accomplish this, you need to acquire the system UUID saved as part of the introspection data for a node:

$ openstack baremetal introspection data save 9dcc87ae-4c6d-4ede-81a5-9b20d7dc4a14 | jq .extra.system.product.uuid

This outputs a system UUID. For example:

"F5055C6C-477F-47FB-AFE5-95C6928C407F"

Use this system UUID in an environment file that defines node-specific hieradata and registers the per_node.yaml template to a pre-configuration hook. For example:

resource_registry:
  OS::TripleO::ComputeExtraConfigPre: /usr/share/openstack-tripleo-heat-templates/puppet/extraconfig/pre_deploy/per_node.yaml
parameter_defaults:
  NodeDataLookup: '{"F5055C6C-477F-47FB-AFE5-95C6928C407F": {"nova::compute::vcpu_pin_set": [ "2", "3" ]}}'

Include this environment file when running openstack overcloud deploy.

The per_node.yaml template generates a set of heiradata files on nodes that correspond to each system UUID and contains the hieradata you defined. If a UUID is not defined, the resulting hieradata file is empty. In the previous example, the per_node.yaml template runs on all Compute nodes (as per the OS::TripleO::ComputeExtraConfigPre hook), but only the Compute node with system UUID F5055C6C-477F-47FB-AFE5-95C6928C407F receives hieradata.

This provides a method of tailoring each node to specific requirements.

In certain circumstances, you might need to install and configure some additional components to your Overcloud nodes. You can achieve this with a custom Puppet manifest that applies to nodes on after the main configuration completes. As a basic example, you might intend to install motd to each node. The process for accomplishing is to first create a Heat template (/home/stack/templates/custom_puppet_config.yaml) that launches Puppet configuration.

heat_template_version: 2014-10-16

description: >
  Run Puppet extra configuration to set new MOTD

parameters:
  servers:
    type: json

resources:
  ExtraPuppetConfig:
    type: OS::Heat::SoftwareConfig
    properties:
      config: {get_file: motd.pp}
      group: puppet
      options:
        enable_hiera: True
        enable_facter: False

  ExtraPuppetDeployments:
    type: OS::Heat::SoftwareDeploymentGroup
    properties:
      config: {get_resource: ExtraPuppetConfig}
      servers: {get_param: servers}

This includes the /home/stack/templates/motd.pp within the template and passes it to nodes for configuration. The motd.pp file itself contains the Puppet classes to install and configure motd.

Next, create an environment file (/home/stack/templates/puppet_post_config.yaml) that registers your heat template as the OS::TripleO::NodeExtraConfigPost: resource type.

resource_registry:
  OS::TripleO::NodeExtraConfigPost: /home/stack/templates/custom_puppet_config.yaml

And finally include this environment file along with your other environment files when creating or updating the Overcloud stack:

$ openstack overcloud deploy --templates \
    ...
    -e /home/stack/templates/puppet_post_config.yaml \
    ...

This applies the configuration from motd.pp to all nodes in the Overcloud.