Development notes

Interfaces

What information is required as input to the cluster/nodes.

Groups:

• login
• compute
• control

Group/host vars:

• Cluster name. Var openhpc_cluster_name. REQUIRED in environment inventory

• Slurmctld address. Var openhpc_slurm_control_host. Default in common:all:openhpc = {{ groups['control'] | first }}. NB: maybe should use .internal_address?

• Partition definitions. Var openhpc_slurm_partitions. Default in common:all:openhpc is single 'compute' partition. NB: requires group "{{ openhpc_cluster_name }}_compute" in environment inventory. Could check groups during validation??

• If using nfs: Var nfs_server. Default in common:all:nfs is nfs_server_default -> "{{ hostvars[groups['control'] | first ].internal_address }}".

• All the "service endpoints" in common:all:defaults:

    elasticsearch_address: "{{ hostvars[groups['opendistro'].0].api_address }}"
    prometheus_address: "{{ hostvars[groups['prometheus'].0].api_address }}"
    openondemand_address: "{{ hostvars[groups['openondemand'].0].api_address if groups['openondemand'] | count > 0 else '' }}"
  

• All the secrets in envionrment:all:secrets - see secret role's defaults:

  • grafana, elasticsearch, mysql (x2) passwords (all potentially depending on group placement)
  • munge key (for all openhpc nodes)

Running install tasks only

Which roles can we ONLY run the install tasks from, to build a cluster-independent(*)/no-config image?

In-appliance roles:

• basic_users: n/a
• block_devices: n/a
• filebeat: n/a but downloads Docker container at service start)
• grafana-dashboards: Downloads grafana dashboards
• grafana-datasources: n/a
• hpctests: n/a but reqd. dnf packages are installed as part of openhpc_default_packages.
• opendistro: n/a but downloads Docker container at service start.
• openondemand:
  • main.yml unnamed task does rpm installs using osc.ood:install-rpm.yml
  • main.yml unnamed task does rpm installs using pam_auth.yml.
  • main.yml [unnamed task] does git downloads using osc.ood:install-apps.yml
  • jupyter_compute.yml: Does yum installs
  • vnc_compute.yml: Does yum installs
• passwords:
• podman

Non-role tasks: openhpc_default_packages: TODO

• It's not really cluster-independent as which features are turned on where may vary.