балансировка нагрузки (вид клиента): как это работает на практике

LB distributes по round-robin / least-connections / consistent hash; health checks self-heal; sticky sessions для WebSocket; TLS termination at LB с X-Forwarded-*.

Разбор

Algorithms: round-robin, least-connections (long streams), IP/consistent hash (stickiness). L7 route by path/header.

Health checks — failing backend out of rotation; zero-downtime deploys via drain → update → add back.

Sticky sessions pin client to backend (cookie or IP hash). Need when server holds per-connection state — WebSocket/SSE on one server, can't move transparently. Stickiness unbalances load; deploy drain kills pinned clients.

TLS termination at LB → plaintext (or re-encrypt) to backends. LB sets true X-Forwarded-For / X-Forwarded-Proto for real client IP/scheme.

Итог

From client view LB = invisible hop; design stateless or sticky + reconnect for long-lived connections.