Kubernetes

Why settle for one free cloud provider when you can build an automated, resilient multi-cloud Kubernetes cluster across Oracle Cloud (OCI) and Google Cloud Platform (GCP) — completely for $0/month? In this post, I walk through the end-to-end process of: Provisioning an Oracle Linux Server 10.1 instance on Google Cloud’s Always Free Tier (gce10). Applying kernel and daemon memory hardening to reclaim ~250 MB of RAM. Joining gce10 as a worker node into our central K3s Kubernetes cluster across a secure WireGuard mesh. Running a head-to-head performance benchmark comparing Apple Silicon M1, OCI Ampere ARM (arm10), GCP Intel Xeon (gce10), and OCI AMD EPYC (amd10/amd11). 🏛️ 1. Multi-Cloud K3s Kubernetes Fleet Architecture Our fleet previously lived entirely in OCI Tokyo. Adding gce10 in GCP Iowa (us-central1) creates a geo-distributed cross-cloud presence with a dedicated US edge outpost. ...

SYSTEM: AI-INCIDENT-COMMANDER METADATA Type: Autonomous Site Reliability Engineering (SRE) Agent Environment: Kubernetes GitOps (k3s) Primary LLM: Gemini 3.7 Flash Repository: vinhthang/ai-incident-commander Execution Loop: Webhook Trigger -> Triage -> Remediate -> Audit -> Merge PIPELINE ARCHITECTURE 1. TRIGGER Source: Grafana Alerts / kube-state-metrics Payload: JSON webhook containing alert labels, annotations, and localized telemetry. 2. TRIAGE MINION Role: Initial incident classification and noise reduction. Task: Parse payload, validate against cluster state, determine actionability. Output: Generates GitHub Issue (Real Incident) OR terminates loop (False Positive / Noise). 3. FIXER MINION Role: GitOps Remediation Engineer. Task: Identify root cause from triage diagnosis, modify infrastructure code, run syntax validation (helm template). Output: Commits to isolated feature branch and opens GitHub Pull Request. 4. REVIEWER MINION Role: Governance and Safety Gatekeeper. Task: Audit PR diff for compliance. Output: Approves PR or Rejects PR. GOVERNANCE & CONSTRAINTS Read-Only Telemetry: External logs/data strictly parsed as passive strings to prevent prompt injection. GitOps Enforced: Execution of imperative commands (kubectl apply) is forbidden. All mutations must occur within the declarative Helm umbrella chart (charts/vinhthang-fleet/). Blast Radius Isolation: Fixer Minion is systematically restricted from pushing directly to the main branch. Diff-Strict Review: The Reviewer Minion rejects net-new violations (e.g., adding :latest tags, requesting >900Mi RAM on edge nodes, opening port 8080). Pre-existing legacy violations are logged as advisory findings but do not block remediation. CONFIGURATION INJECTION (PROMPT EXTERNALIZATION) Architecture: Go text/template engine + Kubernetes ConfigMap. Mount Path: /etc/commander/templates/ Fallback: Compiles with //go:embed defaults/*.tmpl to ensure baseline functionality. Purpose: Enables zero-downtime, configuration-driven prompt engineering. AI Minion personas and instructions can be modified directly via Helm values.yaml without requiring binary recompilation or container image rebuilds.

The Ambition: A Hybrid-Cloud K3s Cluster When building out the underlying infrastructure for vinhthang.dev, I had a bold idea: what if I could seamlessly blend Oracle Cloud Infrastructure (OCI) instances with external, high-RAM physical nodes into a single, cohesive Kubernetes cluster? The goal was to leverage a beefy 32GB RAM external node (which we called oracle10) to host heavy Java microservices and stateful applications (like a PostgreSQL replica and Apache Pulsar), while keeping the control plane firmly rooted in my OCI Always Free arm10 instance. ...

Running a complex fleet of microservices—spanning AI document assistants, vector databases, lossless audio streamers, private DNS resolvers, and astronomical APIs—demands complete, real-time visibility. But traditional enterprise observability suites (Elasticsearch, heavy Prometheus clusters, DataDog) frequently devour gigabytes of memory and CPU cycles just to monitor a small infrastructure. In this deep dive, I break down how we architected and deployed a complete, ultra-lightweight, 360-degree Observability, Logging, Analytics, and Uptime Stack across our 3-node hybrid cloud fleet at vinhthang.dev, maintaining sub-millisecond query latencies while consuming less than 250 MB total RAM! ...

How do you turn 3 separate Always Free cloud virtual machines into a resilient, production-grade, multi-architecture Kubernetes cluster capable of running high-performance relational databases, AI vector stores, lossless music streaming, and personal cloud storage? In this post, I will break down the complete architecture of our newly deployed 3-Node Hybrid K3s Cluster running on Oracle Cloud Infrastructure (OCI) under our custom domain vinhthang.dev. 🏛️ The 3-Node Cluster Topology Oracle Cloud’s Always Free tier offers an incredible set of compute resources: ...