ansible-role-interlink

Ansible role to install and configure InterLink components for Slurm and Kubernetes.

The role supports two execution modes:

• interlink_type_of_node: slurm: installs InterLink API + Slurm plugin, generates mTLS certificates, and exports client artifacts.
• interlink_type_of_node: kubernetes: deploys the InterLink Virtual Kubelet via Helm using artifacts generated in Slurm mode.

What This Role Does

Slurm mode

• Installs required packages (ca-certificates, curl, jq, openssl).
• Creates InterLink directories under interlink_base_dir.
• Downloads InterLink binaries and installs them under interlink_base_dir/bin.
• Generates CA/server/client mTLS certificates with community.crypto.
• Templates InterLink and Slurm plugin configuration files.
• Templates and manages systemd units:
  • interlink-api.service
  • interlink-slurm-plugin.service
• Validates local mTLS endpoint (/pinglink).
• Exports Kubernetes client cert artifacts to:
  • {{ interlink_artifact_dir }}/ca.crt
  • {{ interlink_artifact_dir }}/tls.crt
  • {{ interlink_artifact_dir }}/tls.key

Kubernetes mode

• Verifies mTLS artifacts exist on the Ansible controller.
• Copies artifacts to target host (interlink_remote_cert_dir).
• Ensures namespace exists.
• Creates or updates TLS secret for Virtual Kubelet.
• Templates Helm values and installs/upgrades InterLink chart from GHCR OCI.
• Waits for rollout.
• Finds and approves pending kubelet-serving CSRs for the InterLink service account.
• Waits for Virtual Kubelet node Ready.
• Optionally runs smoke test pod (interlink_run_smoke_test: true).

Requirements

• Ansible >= 2.12
• Collection:
  • community.crypto
• External tools expected on target hosts:
  • Slurm mode: curl, openssl, jq (installed by role), systemd available.
  • Kubernetes mode: kubectl, helm, jq available in PATH.
• Access to Kubernetes admin kubeconfig (kubeconfig_path, default /etc/kubernetes/admin.conf).

Role Variables

Defaults are defined in defaults/main.yml.

Core mode and identity

• interlink_type_of_node (default: kubernetes): kubernetes or slurm.
• type_of_node: backward-compatible alias.
• interlink_namespace (default: interlink)
• interlink_node_name (default: interlink-slurm-vk)
• interlink_run_smoke_test (default: false)

Paths and runtime

• interlink_base_dir (default: /opt/interlink)
• interlink_data_dir (default: {{ interlink_base_dir }}/data)
• interlink_work_dir (default: {{ interlink_base_dir }}/work)
• interlink_home_dir (default: {{ interlink_base_dir }}/home)
• interlink_artifact_dir (default: {{ playbook_dir }}/artifacts/{{ interlink_node_name }})
• interlink_remote_cert_dir (default: /tmp/{{ interlink_node_name }}-certs)
• kubeconfig_path (default: /etc/kubernetes/admin.conf)

Versions and image

• interlink_version (default: 0.6.1-patch1)
• interlink_slurm_plugin_version (default: 0.6.1)
• interlink_chart_version (default: 0.6.1)
• virtual_kubelet_image (default: ghcr.io/interlink-hq/interlink/virtual-kubelet-inttw:0.6.1-patch1)

Capacity and resource settings

• virtual_node_cpu (default: 1)
• virtual_node_memory_gib (default: 1)
• virtual_node_pods (default: 10)
• virtual_kubelet_cpu_request (default: 100m)
• virtual_kubelet_cpu_limit (default: 500m)
• virtual_kubelet_memory_request (default: 128Mi)
• virtual_kubelet_memory_limit (default: 512Mi)

Slurm defaults

• slurm_partition (default: debug)
• slurm_default_cpu (default: 1)
• slurm_default_memory (default: 1G)
• slurm_job_time (default: 00:10:00)

Recommended Deployment Flow

Run the role in two phases:

1. Execute with interlink_type_of_node: slurm on your Slurm-side host.
2. Execute with interlink_type_of_node: kubernetes on your Kubernetes-side host.

The Kubernetes phase consumes artifacts exported by the Slurm phase from interlink_artifact_dir.

Example Playbook: Slurm

- name: Deploy InterLink on Slurm host
  hosts: slurm_frontend
  become: true
  roles:
    - role: grycap.interlink
      vars:
        interlink_type_of_node: slurm
        interlink_node_name: interlink-slurm-vk

Example Playbook: Kubernetes

- name: Deploy InterLink Virtual Kubelet on Kubernetes host
  hosts: k8s_frontend
  become: true
  roles:
    - role: grycap.interlink
      vars:
        interlink_type_of_node: kubernetes
        interlink_node_name: interlink-slurm-vk
        interlink_namespace: interlink
        interlink_run_smoke_test: true

Dependency Role

meta/main.yml declares a conditional dependency:

• usegalaxy_eu.apptainer when running in Slurm mode.

Troubleshooting

• Error about missing mTLS artifacts in Kubernetes mode:
  • Run Slurm mode first, then verify files exist in interlink_artifact_dir.
• CSR approval does not happen:
  • Verify jq is installed and the service account name matches system:serviceaccount:<namespace>:<interlink_node_name>.
• Helm install/upgrade fails:
  • Verify helm supports OCI and can access ghcr.io.

License

Apache-2.0