This is the autoscale loop, drawn from prod-eu-a. Every path on the diagram is a real wire in production. Versions are pinned to substrate 7.2 as of 2026-01-30; the bill of materials is at the bottom of the page and matches what's running right now.
prometheus alertmanager fires autoscale.cpu.hi on vm-pool/web. CPU 72% across 8 vCPU domains, queue depth 240 at HAProxy. Alert webhook hits the policy gate on prod-eu-a.
Gate reads the org contract: quota 100 vCPU · 480 GiB, cap +10%, signed 2025-11-02. Projection of post-scale usage: 9/110 vCPU committed = 82% of envelope. Within cap.
Gate calls oneflow.scale("web", +1). Scheduler picks r3.05.nd-04a2c1 in zone-b (least-loaded NUMA node). OpenNebula provisions a KVM domain from the warm template; bootdisk on Ceph RBD, ephemeral local NVMe attached.
Domain passes liveness on first probe (28 seconds post-spawn). Cilium adds the pod IP to the BGP-announced backend set for VIP 10.10.4.12/32. HAProxy 2.8 reloads via runtime API.
HAProxy reload complete. Zero dropped connections. Traffic balanced across 9 backends. CPU on the pool drops to 58% over the next 30 s.
Event evt-7f3a91 signed (ed25519, key policy-gate-2026-q1), appended to org acme-tickets's ledger. Audit line includes contract version, projection numbers, scheduler decision, and zone placement. End-to-end: 51.94 s.
If a subsequent trigger had asked for an 11th vCPU, the gate would have projected 11/110 = 110.1% of envelope. Provisioning call refused with HTTP 429, response includes contract violation reason. Mail dispatched to org owner within 30 s. Ledger appended with refusal line.
| Component | Version | Role | Pin / source |
|---|---|---|---|
| OpenNebula | 7.2.0 | core orchestrator, OneFlow services | apt · vendor repo |
| Ceph | Reef 18.2.4 | RGW + RBD + CephFS | cephadm |
| Cilium | 1.19.0 | CNI · BGP control plane | helm chart, pinned digest |
| HAProxy | 2.8.12 LTS | ingress · runtime API | vendor repo |
| Kubernetes | 1.30.4 | managed clusters | kubeadm · in-house image |
| Linux kernel | 6.6 LTS | host kernel · all racks | Debian backport, frozen |
| KVM / libvirt | 9.0 / 10.4 | VM substrate | Debian stable |
| etcd | 3.5.13 | k8s control plane backing store | in-house image |
| Prometheus | 2.51.1 | per-org metrics | helm · in-house chart |
| Alertmanager | 0.27.0 | per-org routing | helm · in-house chart |