keepalived

查看keepalived状态

systemctl status keepalived

查看浮动IP情况

ip addr show

备机：

主备切换逻辑

关键配置文件/etc/keepalived/keepalived.conf

系统日志/var/log/messages

监控脚本/usr/local/bin/check_9090.sh

keepalived日志

journalctl -u keepalived -f

主备切换失败原因

主的/etc/keepalived/keepalived.conf配置文件，中priority基础值100，weight=2，所以即便失败其值为100，成功102

而备的priority基础值90，weight=2，92无论如何无法超过100，备无法成为主

修改如下：主、备

vrrp_script chk_service {
script "/usr/local/bin/check_9090.sh"
interval 2
weight 10
fall 3
rise 2
}

vrrp_instance VI_1 {
state MASTER
interface eth0  # 替换为实际网卡
virtual_router_id 51
priority 100
advert_int 1

global_defs {
router_id LVS_BACKUP
}

vrrp_script chk_service {
script "/usr/local/bin/check_9090.sh"
interval 2
weight 10
fall 3
rise 2
}

vrrp_instance VI_1 {
state BACKUP
interface eth0  # 替换为实际网卡
virtual_router_id 51
priority 95
advert_int 1

启用开机自动启动

为了确保服务器重启后 keepalived 能自动运行，您需要在主备两台服务器上都执行以下命令：

systemctl enable keepalived

这个命令的作用是建立软链接，将 keepalived 服务添加到系统启动时自动运行的序列中。

执行后，您会看到类似输出：

Created symlink from /etc/systemd/system/multi-user.target.wants/keepalived.service to /usr/lib/systemd/system/keepalived.service.

验证是否设置成功：

再次运行 systemctl status keepalived，查看 Loaded一行，如果成功，会显示 enabled，例如：

Loaded: loaded (/usr/lib/systemd/system/keepalived.service; enabled; vendor preset: disabled)