# 高可用技术
Pacemaker + Corosync：集群资源管理
Keepalived：VIP漂移
HAProxy：负载均衡

# 启动pcs服务
$ sudo systemctl start pcsd
$ sudo systemctl enable pcsd

# 设置hacluster用户密码
$ sudo passwd hacluster

# 节点认证
$ sudo pcs cluster auth node1 node2 -u hacluster -p password

# 创建集群
$ sudo pcs cluster setup mycluster node1 node2

# 启动集群
$ sudo pcs cluster start –all

# 查看集群状态
$ sudo pcs status
Cluster name: mycluster
Stack: corosync
Current DC: node1 (version 2.0.3-5.el8) – partition with quorum
Last updated: Mon Apr 6 10:00:00 2026
Last change: Mon Apr 6 10:00:00 2026 by hacluster via crmd on node1

2 nodes configured
0 resources configured

Online: [ node1 node2 ]

# 配置VIP资源
$ sudo pcs resource create VirtualIP ocf:heartbeat:IPaddr2 \
ip=192.168.1.100 cidr_netmask=24 op monitor interval=30s

# 配置Web服务资源
$ sudo pcs resource create WebServer ocf:heartbeat:apache \
configfile=/etc/httpd/conf/httpd.conf op monitor interval=30s

# 配置资源约束
$ sudo pcs constraint colocation add WebServer with VirtualIP INFINITY
$ sudo pcs constraint order VirtualIP then WebServer

# 查看资源配置
$ sudo pcs resource show
VirtualIP (ocf::heartbeat:IPaddr2): Started node1
WebServer (ocf::heartbeat:apache): Started node1

# 1. 环境准备
# node1: 192.168.1.10
# node2: 192.168.1.11
# VIP: 192.168.1.100

# 2. 安装软件
$ sudo dnf install pacemaker corosync pcs httpd -y

# 3. 配置集群
$ sudo pcs cluster setup webcluster node1 node2
$ sudo pcs cluster start –all

# 4. 配置资源
$ sudo pcs resource create VIP ocf:heartbeat:IPaddr2 ip=192.168.1.100
$ sudo pcs resource create HTTP ocf:heartbeat:apache

# 5. 测试故障转移
$ sudo pcs cluster standby node1
$ sudo pcs status
Online: [ node2 ]