前言
nginx使用docker部署；keepalived使用传统部署。 准备两台服务器：192.168.1.6 和192.168.1.7
部署keepalived
keepalived可以将多个无状态的单点通过虚拟IP(VIP)漂移的方式搭建成一个高可用服务
这里下载最新的版本V2.2.7：
- 先决条件-安装基础依赖
-
#RHEL/CentOS
yum install curl gcc openssl-devel libnl3-devel net-snmp-devel
# Ubuntu
apt-get install curl gcc libssl-dev libnl-3-dev libnl-genl-3-dev libsnmp-dev
tar -xzvf keepalived-2.2.7.tar.gz
cd keepalived-2.2.7
./configure --prefix=/usr/local/keepalived-2.2.7 --sysconf=/etc
prefix：keepalived安装位置
sysconf：keepalived配置文件位置，默认/etc
编译
make
安装
sudo make install
配置
创建/etc/keepalived/keepalived.conf配置文件：
主节点(MASTER)的配置：
global_defs { router_id LVS_DEVEL } vrrp_instance VI_1 { state MASTER interface ens33 virtual_router_id 1 priority 100 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.1.100 } }
子节点(BACKUP)的配置：
global_defs { router_id LVS_DEVEL } vrrp_instance VI_1 { state BACKUP interface ens33 virtual_router_id 2 priority 90 advert_int 1 nopreemt authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.1.100 } }
解释：
state MASTER 表示该节点为主节点；
virtual_router_id 1 虚拟路由id，取值范围0-255，主节点(MASTER)和子节点(BACKUP)不要设置一致；
interface ens33 指定网卡名称，使用ip addr查看；
advert_int 1 主、子节点心跳频率，单位为秒
mcast_src_ip 192.168.1.6 指定节点的IP地址；
authentication 用户名密码，主节点(MASTER)和子节点(BACKUP)设置一致；
virtual_ipaddress { 192.168.1.100 }虚拟IP（VIP）地址，待会测试就是使用该IP地址访问；最好跟服务器同一个网段；主节点(MASTER)和子节点(BACKUP)设置一致；
创建
keepalived.service 文件
[Unit] Description=Keepalived After=network.target [Service] ExecStart=/usr/local/keepalived-2.2.7/sbin/keepalived -D ExecReload=/bin/kill -HUP $MAINPID KillMode=process Restart=on-failure Type=forking [Install] WantedBy=multi-user.target
请确保将
ExecStart 的路径 /usr/local/keepalived-2.2.7/sbin/keepalived 替换为你 Keepalived 实际安装的路径将创建的
keepalived.service 文件移动到 /etc/systemd/system/ 目录中：
sudo mv keepalived.service /etc/systemd/system/
重新加载 systemd 配置
sudo systemctl daemon-reload
启动 Keepalived 服务
sudo systemctl start keepalived
重启
systemctl restart keepalived
停止
systemctl stop keepalived
查看运行状态
systemctl status keepalived
开机自启
systemctl enable keepalived
主节点和子节点都启动keepalived，通过VIP访问，默认访问到主节点