nginx+keepalived实现高可用

# 主机keepalived配置cd /etc/keepalived
cat keepalived.conf
! Configuration File for keepalived
global_defs {
    router_id balance01       #xx主备id    enable_script_security
    script_user root
}
#加入周期性检测nginx服务脚本的相关配置vrrp_script check_nginx {
    script "/etc/keepalived/check_nginx.sh"#心跳执行的脚本，检测nginx是否启动    interval 2#（检测脚本执行的间隔，单位是秒）}
vrrp_instance VI_1 {
    state BACKUP
    interface eth0   #网卡名称    virtual_router_id 51    priority 99#优先级，主不改，备改成比100小就行    advert_int 1    authentication {
        auth_type PASS
        auth_pass NgLMwBmE
    }
    unicast_src_ip 192.168.0.19 #这里是主服务器私网ip    unicast_peer {
192.168.0.56      #备服务器的私网ip，如果有多个，可以换行添加（对端ip，比如主的这里写备的内网ip）    }
    virtual_ipaddress {
192.168.0.120 label eth0:0
    }
#添加跟踪(执行脚本)    track_script {
        check_nginx
    }
}
# 备机keepalived配置! Configuration File for keepalived
global_defs {
    router_id balance01       #xx主备id    enable_script_security
    script_user root
}
#加入周期性检测nginx服务脚本的相关配置vrrp_script check_nginx{
    script "/etc/keepalived/check_nginx.sh"#心跳执行的脚本，检测nginx是否启动    interval 2#（检测脚本执行的间隔，单位是秒）}
vrrp_instance VI_1 {
    state MASTER
    interface eth0   #网卡名称    virtual_router_id 51    priority 100#优先级，主不改，备改成比100小就行    advert_int 1    authentication {
        auth_type PASS
        auth_pass NgLMwBmE
    }
    unicast_src_ip 192.168.0.56 #这里是主服务器私网ip    unicast_peer {
192.168.0.19      #备服务器的私网ip，如果有多个，可以换行添加（对端ip，比如主的这里写备的内网ip）    }
    virtual_ipaddress {
192.168.0.120 label eth0:0
    }
    添加跟踪(执行脚本)
    track_script{
        check_nginx
    }
}
# chech_nginx.sh脚本#!/bin/bash#检查nginx进程是否存在count=$(ps -C nginx --no-heading | wc -l)#进程数等于0的时候if [ "${count}"="0" ]; then#尝试启动一次nginx，停止2秒后再次检测    /home/ops/server/nginx/sbin/nginx
sleep2count=$(ps -C nginx --no-heading | wc -l)if [ "${count}"="0" ]; then#如果启动没成功，就杀掉keepalive触发主备切换        systemctl stop keepalived
fifi

systemctl enable keepalived
systemctl start keepalived

ifconfig -aeth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500        inet 192.168.0.56  netmask 255.255.255.0  broadcast 192.168.0.255
        inet6 fe80::f816:3eff:fe76:ce06  prefixlen 64  scopeid 0x20<link>
        ether fa:16:3e:76:ce:06  txqueuelen 1000  (Ethernet)
        RX packets 423293  bytes 233312508 (233.3 MB)
        RX errors 0  dropped 0  overruns 0  frame 0        TX packets 437023  bytes 331280752 (331.2 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0eth0:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500        inet 192.168.0.120  netmask 255.255.255.255  broadcast 0.0.0.0
        ether fa:16:3e:76:ce:06  txqueuelen 1000  (Ethernet)
lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 78258  bytes 8896394 (8.8 MB)
        RX errors 0  dropped 0  overruns 0  frame 0        TX packets 78258  bytes 8896394 (8.8 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0