infra/docs
Viktor Barzin 7cb44d7264 [registry] Stop recurring orphan OCI-index incidents — detection + prevention + recovery
Second identical registry incident on 2026-04-19 (first 2026-04-13): the
infra-ci:latest image index resolved to child manifests whose blobs had been
garbage-collected out from under the index. Pipelines P366→P376 all exited
126 "image can't be pulled". Hot fix (a05d63e / 6371e75 / c113be4) restored
green CI but left the underlying bug unaddressed.

Root cause: cleanup-tags.sh rmtrees tag dirs on the registry VM daily at
02:00, registry:2's GC (Sunday 03:25) walks OCI index children imperfectly
(distribution/distribution#3324 class). Nothing verified pushes end-to-end;
nothing probed the registry for fetchability; nothing caught orphan indexes.

Phase 1 — Detection:
 - .woodpecker/build-ci-image.yml: after build-and-push, a verify-integrity
   step walks the just-pushed manifest (index + children + config + every
   layer blob) via HEAD and fails the pipeline on any non-200. Catches
   broken pushes at the source.
 - stacks/monitoring: new registry-integrity-probe CronJob (every 15m) and
   three alerts — RegistryManifestIntegrityFailure,
   RegistryIntegrityProbeStale, RegistryCatalogInaccessible — closing the
   "registry serves 404 for a tag that exists" gap that masked the incident
   for 2+ hours.
 - docs/post-mortems/2026-04-19-registry-orphan-index.md: root cause,
   timeline, monitoring gaps, permanent fix.

Phase 2 — Prevention:
 - modules/docker-registry/docker-compose.yml: pin registry:2 → registry:2.8.3
   across all six registry services. Removes the floating-tag footgun.
 - modules/docker-registry/fix-broken-blobs.sh: new scan walks every
   _manifests/revisions/sha256/<digest> that is an image index and logs a
   loud WARNING when a referenced child blob is missing. Does NOT auto-
   delete — deleting a published image is a conscious decision. Layer-link
   scan preserved.

Phase 3 — Recovery:
 - build-ci-image.yml: accept `manual` event so Woodpecker API/UI rebuilds
   don't need a cosmetic Dockerfile edit (matches convention from
   pve-nfs-exports-sync.yml).
 - docs/runbooks/registry-rebuild-image.md: exact command sequence for
   diagnosing + rebuilding after an orphan-index incident, plus a fallback
   for building directly on the registry VM if Woodpecker itself is down.
 - docs/runbooks/registry-vm.md + .claude/reference/service-catalog.md:
   cross-references to the new runbook.

Out of scope (verified healthy or intentionally deferred):
 - Pull-through DockerHub/GHCR mirrors (74.5% hit rate, no 404s).
 - Registry HA/replication (single-VM SPOF is a known architectural
   choice; Synology offsite covers RPO < 1 day).
 - Diun exclude for registry:2 — not applicable; Diun only watches
   k8s (DIUN_PROVIDERS_KUBERNETES=true), not the VM's docker-compose.

Verified locally:
 - fix-broken-blobs.sh --dry-run on a synthetic registry directory correctly
   flags both orphan layer links and orphan OCI-index children.
 - terraform fmt + validate on stacks/monitoring: success (only unrelated
   deprecation warnings).
 - python3 yaml.safe_load on .woodpecker/build-ci-image.yml and
   modules/docker-registry/docker-compose.yml: both parse clean.

Closes: code-4b8

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-19 17:08:28 +00:00
..
architecture [docs] TrueNAS decommission cleanup — remove references from active docs 2026-04-19 16:55:43 +00:00
plans [docs] Update anti-AI and rybbit docs after rewrite-body removal 2026-04-17 21:43:13 +00:00
post-mortems [registry] Stop recurring orphan OCI-index incidents — detection + prevention + recovery 2026-04-19 17:08:28 +00:00
runbooks [registry] Stop recurring orphan OCI-index incidents — detection + prevention + recovery 2026-04-19 17:08:28 +00:00
README.md [docs] TrueNAS decommission cleanup — remove references from active docs 2026-04-19 16:55:43 +00:00

Infrastructure Documentation

This repository contains the configuration and documentation for a homelab Kubernetes cluster running on Proxmox. The infrastructure hosts 70+ services managed declaratively with Terraform and Terragrunt.

Quick Reference

Network Ranges

  • Physical Network: 192.168.1.0/24 - Physical devices and host network
  • Management VLAN 10: 10.0.10.0/24 - Infrastructure VMs and management
  • Kubernetes VLAN 20: 10.0.20.0/24 - Kubernetes cluster network

Key URLs

  • Public: viktorbarzin.me
  • Internal: viktorbarzin.lan

Architecture Documentation

Document Description
Overview Infrastructure overview, hardware specs, VM inventory, and service catalog
Networking Network topology, VLANs, routing, and firewall rules
VPN Headscale mesh VPN and Cloudflare Tunnel configuration
Storage Proxmox host NFS, Proxmox CSI (LVM-thin + LUKS2), and persistent volume management
Authentication Authentik SSO, OIDC flows, and service integration
Security CrowdSec IPS, Kyverno policies, and security controls
Monitoring Prometheus, Grafana, Loki, and observability stack
Secrets Management HashiCorp Vault integration and secret rotation
CI/CD Woodpecker CI pipeline and deployment automation
Backup & DR Backup strategy, disaster recovery, and restore procedures
Compute Proxmox VMs, GPU passthrough, K8s resource management, and VPA
Databases PostgreSQL, MySQL, Redis, and database operators
Multi-tenancy Namespace isolation, tier system, and resource quotas

Operations

  • Runbooks - Step-by-step operational procedures
  • Plans - Infrastructure change plans and rollout strategies

Getting Started

  1. Review the Overview for a high-level understanding
  2. Read the Networking doc to understand connectivity
  3. Check Compute for resource management patterns
  4. Explore individual architecture docs based on your area of interest