Apache s mod_jk slouzil jako load balancer, ale s rostoucim trafficem hledame lepsi reseni. HAProxy je de facto standard — rychly, spolehlive a s vynikajici konfiguraci.
Proc HAProxy¶
Lepsi health checks, detailni statistiky (real-time dashboard), nizsi resource footprint, lepsi sticky session management. Dediklovany load balancer vs. web server s LB funkci.
Konfigurace¶
Frontend, backend, health check na /health endpoint. Sticky sessions pres cookie SERVERID. Automaticky failover.
Zero-downtime deployment¶
Rolling deployment: vyradit server A, upgradovat, vratit do poolu, pak server B. CLI: set server state drain.
Zaverem¶
HAProxy je vyborny load balancer. Stats dashboard a CLI umoznuji operacni flexibilitu, kterou Apache nenabizi.