一、keepalived介绍 LB(Load Balance) #负载均衡 #lvs/HAProxy/nginx（http/upstream, stream/upstream ） HA(High Availability) #高可用集群，数据库、Zookeeper、Redis SPoF: Single Point of Failure，解决单点故障 HPC #高性能集群(High Performance Computing) https://www.top500.org 系统可用性：SLA(Service-Level 95%=(60*24*30)*(1-0.9995) （指标）=99.9%, ..., 99.999%，99.9999% 提升系统高用性的解决方案之降低MTTR- Mean Time To Repair(平均故障时间) 解决方案：建立冗余机制 active/passive 主/备 active/active 双主 active --> HEARTBEAT --> passive active <--> HEARTBEAT <--> ....