GEM Infrastructure Manual¶
Operations documentation for the GEM Kubernetes platform, GitOps deployment flow, and application workloads.
GitOps first
Persistent infrastructure and application changes should be made in Git and reconciled by Rancher Fleet. Avoid long-lived manual changes in Rancher or directly on Kubernetes resources.
Quick Access¶
| Area | Link | Use |
|---|---|---|
| Cluster management | Rancher | Manage clusters, Fleet bundles, workloads, access, and Rancher apps. |
| Source and CI | GitLab | Work with repositories, CI pipelines, and the container registry. |
| Monitoring | Grafana | Inspect dashboards and operational metrics. |
| Automation | Semaphore UI | Run infrastructure automation and Ansible workflows. |
| Production app | Moodle Production | Open the production Moodle environment. |
| Development app | Moodle Development | Open the development Moodle environment. |
System Overview¶
The infrastructure is operated as GitOps: source repositories define desired state, CI builds artifacts, and Rancher Fleet reconciles Kubernetes workloads from the Fleet repository.
Tool Layers¶
The platform is organized into source, control-plane, Kubernetes platform, and workload layers.
Main Workflows¶
| Workflow | Start Here | Primary Tools |
|---|---|---|
| Understand the cluster layout | General overview | Rancher, Fleet, Kubernetes |
| Prepare operator access | Getting started | SSH, kubeconfig, Rancher |
| Run infrastructure automation | Ansible overview | Ansible, Semaphore UI |
| Deploy or inspect Fleet apps | Fleet docs | Rancher Fleet, GitLab |
| Investigate runtime issues | Grafana and Rancher | Grafana, Rancher, kubectl |
| Manage hardware or nodes | Manage hardware | Rancher, SSH, Kubernetes |
Platform Inventory¶
| Tool | URL | Purpose | Source |
|---|---|---|---|
| Infrastructure Docs | infra-docs.gem.mintfit.hamburg | This documentation site. | infrastructure/docs, deployed by infrastructure/fleet/docs |
| Rancher | rancher.gem.mintfit.hamburg | Kubernetes management UI for clusters, Fleet, workloads, and access. | management cluster |
| GitLab | gitlab.gem.mintfit.hamburg | Source repositories, CI pipelines, and container registry. | platform service |
| Semaphore UI | semaphore.gem.mintfit.hamburg | Automation UI for infrastructure tasks and Ansible workflows. | infrastructure/fleet/semaphore |
| Grafana | grafana.gem.mintfit.hamburg | Monitoring dashboards exposed through an authenticated ingress. | infrastructure/fleet/grafana |
| Longhorn | Rancher UI | Distributed block storage and persistent volume management. | Rancher app, longhorn-system |
| k6 | Rancher UI | Load testing tooling for Kubernetes-based performance checks. | Rancher app |
| Moodle Production | moodle.gem.mintfit.hamburg | Production Moodle application. | infrastructure/fleet/moodle-prod |
| Moodle Development | moodle-development.gem.mintfit.hamburg | Development Moodle application. | infrastructure/fleet/moodle-dev |
Documentation Sources¶
This site is built from the infrastructure/docs repository. During CI, it pulls selected READMEs from the owning source repositories:
development/ansibleinfrastructure/fleetinfrastructure/general
The generated MkDocs site is packaged as a static container image and deployed through the infrastructure/fleet/docs bundle.