8aa400a5d4
Add 37 new entries and update 7 existing entries across 13 topic files. Major contributions from agent-runtimes (K8s secrets, CI, Docker gotchas), cluster-bootstrap (ArgoCD SSA, etcd tuning, DB migrations, Compose networking), and cluster-apps/octopus-deploy (Helm vs raw manifests, ArgoCD source types). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
1.8 KiB
1.8 KiB
Helm Charts
Schema Validation
- Always validate values against the chart schema before committing. Run
helm show values <repo>/<chart> --version <ver>to check the actual structure. - Helm chart schemas change between versions — field names and nesting can differ from documentation or online examples.
- A quick
helm templatetest locally catches schema errors before deployment. additionalProperties: falsein chart schemas means any extra keys at the wrong nesting level cause a hard failure.
Version Verification
- Run
helm search repoor check upstream docs to confirm latest stable versions - Don't rely on memory for chart versions — they go stale quickly
- Check compatibility matrices between chart version, app version, and other cluster components
Multi-Source Applications
- ArgoCD multi-source Applications use
$refsyntax to combine external Helm charts with Git-stored values files - Keep values files in Git alongside the ArgoCD Application manifest
Timeout Handling
- Under cluster pressure (many events, etcd busy), default Helm timeouts may not be enough
- Increase timeout for initial installs (e.g., 10m instead of 5m)
helm upgrade --installis idempotent — retries are safe
Prefer Raw Manifests Over Complex Helm Charts for Simple Workloads
When a Helm chart introduces infrastructure dependencies beyond the application itself (NFS servers, CSI drivers, pre-install hooks with trust bootstrapping, RWX PVC requirements), evaluate whether a raw Deployment or StatefulSet with environment variables would be simpler. Complex charts that bundle infrastructure assumptions are fragile on non-standard clusters. If the application image handles its own configuration via env vars, a raw manifest is often more reliable and debuggable.