If you've ever stared at a production alert screaming `token is not renewable` at 2 AM, you know the particular joy of Vault token management. These errors...
If you've spent any time with Prometheus, you've seen it. That red `DOWN` label in the Targets page, accompanied by the dreaded `connection refused` error....
If you've ever stared at this error message in your logs, you know the frustration: It's one of those errors that looks simple on the surface but has about...
Split-brain in Keepalived means both nodes think they own the VIP. Traffic gets blackholed or split unpredictably. Here's how to diagnose and fix it fast....
How to use Apache httpd as a reverse proxy with mod_proxy — proxying to backend services, load balancing across multiple upstreams, WebSocket proxying, and health check configuration.
How to configure Apache httpd for production use — name-based virtual hosts, SSL/TLS with Let's Encrypt, HTTP to HTTPS redirects, mod_rewrite rules, and performance tuning with MPM.
An introduction to Envoy Proxy's architecture — listeners, clusters, filters, and the xDS dynamic configuration API. Covers static configuration for standalone use and how Envoy fits into service meshes like Istio.
Advanced Envoy traffic management — configuring retries with exponential backoff, per-request timeouts, weighted canary routing, global rate limiting, and fault injection for resilience testing.
Advanced HAProxy SSL configuration — multi-domain SNI routing from a single frontend, mutual TLS (mTLS) for service-to-service authentication, certificate management, and OCSP stapling.
A comprehensive HAProxy configuration guide covering frontends, backends, balance algorithms, active health checks, SSL termination, ACLs, rate limiting, and the runtime socket API.
Step-by-step guide to building a highly available load balancer pair with HAProxy and Keepalived — covering the full stack from VIP configuration to health checks, stats, and SSL termination.
How to configure Keepalived for automatic failover using VRRP — setting up master/backup pairs, virtual IPs, health-check scripts, and combining it with HAProxy or Nginx for zero-downtime load balancer HA.
A practical DNS troubleshooting guide for DevOps engineers — dig commands, nslookup patterns, common production failure modes, and how to diagnose each one.
How to implement zero-trust pod-to-pod communication in Kubernetes using NetworkPolicies — deny by default, allow explicitly, and validate it works.