OpenStack Cluster-as-a-Service Infrastructure

This role generates software-defined OpenStack infrastructure that can be used for generating complex application topologies on demand. A recent version of OpenStack Heat is used to achieve this.

Requirements

The OpenStack APIs should be accessible from the target host. OpenStack Newton or later is required. Client credentials should have been set in the environment, or using the clouds.yaml format.

Role Variables

cluster_venv: Optional path to a python virtualenv in which the python shade package is installed.

cluster_auth_type: Optional name of the OpenStack authentication plugin to use.

cluster_auth: Optional dictionary containing authentication information.

cluster_cloud: Optional name of the OpenStack client config cloud name to use.

cluster_state: Desired state of the cluster, either present or absent. The default value is present.

cluster_name: Name to give the Heat stack It defaults to cluster

cluster_environment_nodenet: An environment file specifying the resource to use for the per-node network, Cluster:NodeNet.

cluster_environment_instance: An environment file specifying the resource to use for the instances, Cluster:Instance.

cluster_environment: A list of environment files to use when creating the Heat stack.

cluster_params: Parameters that are passed in to the Heat stack.

• cluster_prefix: Name prefix to use for instance hostname construction.

• cluster_groups: JSON-structured list of node groups, each of which is described by a dict, containing the following:

  • name: A name to refer to this group
  • flavor: The name or UUID of an instance flavor to use for deploying this group.
  • image: The name or UUID of an image to use for deploying this group.
  • user: The name of a cloud user for which SSH keys have been provisioned and passwordless sudo has been configured. Could be (for example), centos, debian or ubuntu.
  • num_nodes: The number of nodes to create within this group.
  • volume_size: Optional size in GB of volumes used to boot instances in this group when the instance-w-volume.yaml environment is used.
  • volume_type: Optional type of volumes used to boot instances in this group when the instance-w-volume.yaml environment is used.

• cluster_keypair: Name of an SSH key pair to use to access the instances.

• cluster_az: Name of the availability zone in which to create the instances.

• cluster_config_drive: Whether to provide metadata via a config drive. Default is false.

• cluster_net: JSON-structure list of networks, each of which is described by a dict, containing the following:

  • net: Name or UUID of a neutron network to attach the instances to.
  • subnet: Name or UUID of a neutron subnet to attach the instances to.
  • security_groups: Optional list of names or UUIDs of security groups to add the instances' ports to.
  • floating_net: Optional name or UUID of a neutron network to attach floating IPs to when the nodenet-w-fip.yaml environment is used.

cluster_inventory: After deployment, an inventory file is generated, which can be used in subsequent Ansible-driven configuration.

cluster_roles: A set of group assignments to make in the Ansible inventory file that is generated. This parameter is a list of dicts of the form:

• name: Name of the group to define in the Ansible inventory.
• groups: A list of groups selected from the dict objects supplied to cluster_groups, above.

cluster_group_vars: A dictionary mapping inventory groups to group variables to be defined for that group. The group variables for each group are defined as a dictionary mapping variable names to their values.

cluster_environment_group: An optional Ansible group name to which all cluster hosts and localhost will be added. This can be useful if there is a single group that represents an environment such as development/staging/production.

Dependencies

This role depends on the python shade package being installed on the target host. The package may be installed in a python virtual environment, in which case the path to the virtualenv should be specified in the cluster_venv variable.

The stackhpc.os-shade role may be used to install the python shade package.

Example Playbook

The following playbook creates a Heat stack for a cluster containing a login group and a compute group.

---
# This playbook uses the Ansible OpenStack modules to create a cluster
# using a number of baremetal compute node instances, and configure it
# for a SLURM partition
- hosts: openstack
  roles:
    - role: stackhpc.cluster-infra
      cluster_name: "openhpc"
      cluster_params:
        cluster_prefix: "ohpc"
        cluster_keypair: "admin_rsa"
        cluster_net:
          - net: "internal"
            subnet: "internal"
        cluster_groups:
          - name: "login"
            flavor: "compute-B"
            image: "CentOS7-OpenHPC"
            num_nodes: 1
          - name: "compute"
            flavor: "compute-A"
            image: "CentOS7-OpenHPC"
            num_nodes: 16
      cluster_group_vars:
        cluster:
          ansible_user: centos

Author Information

• Stig Telfer ([email protected])