下载包 下载地址 https://www.keepalived.org/software/keepalived-2.0.20.tar.gz
解压缩 tar -zxvf keepalived-2.0.20.tar.gz
进入到解压完的目录 cd keepalived-2.0.20
准备环境
安装openssl-devel
yum -y install openssl-devel
安装gcc
yum -y install gcc
安装
./configure --prefix=/usr/local/keepalived
make && make install
安装完成后系统会在/usr/local/keepalived目录下生成 bin etc sbin share 这 4 个文件夹。 配置文件(keepalived.conf)在 /usr/local/keepalived/etc/keepalived 这个路径下
拷贝配置文件
mkdir -p /etc/keepalived/ *keepalived启动时默认去这个路径加载配置文件*
cp keepalived/etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf
复制后就可以操作/etc/keepalived/keepalived.conf文件了
配置文件
主配置文件
global_defs {
router_id NodeA
vrrp_skip_check_adv_addr
vrrp_garp_interval 0
vrrp_gna_interval 0
}
vrrp_script check_script {
script "/etc/keepalived/check_nginx.sh 80"
interval 10
}
vrrp_instance VI_1 {
state MASTER
interface ens33
virtual_router_id 131
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.152.131
}
}
从配置文件
global_defs {
router_id NodeB
vrrp_skip_check_adv_addr
vrrp_garp_interval 0
vrrp_gna_interval 0
}
vrrp_script check_script {
script "/etc/keepalived/check_nginx.sh 80"
interval 10
}
vrrp_instance VI_1 {
state BACKUP
interface ens33
virtual_router_id 131
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.152.131
}
}
按同样的方法配置节点B并修改配置文件，可将A节点的配置文件复制到B节点，并修改以下几项：
router_id NodeB
state BACKUP
priority 99
其它项不必修改。
启动keepalived
/usr/local/keepalived/sbin/keepalived -D
查看进程
ps aux | grep keepalived
Keepalived 正常运行时，共启动 3 个进程，其中一个进程是父进程，负责监控其子进程；一个是 vrrp 子进程；另外一个是 checkers 子进程
查看虚拟IP是否已经绑定到网卡上
ip a
常用命令
systemctl restart keepalived
配置nginx主从切换
将写好的脚本复制到/etc/keepalived/文件夹下*就是keepalived的配置文件内配置的 vrrp_script check_script 节点*
脚本内容
#!/bin/bash
#author:liudan
#description:check nginx service
port=$1
count=0
for (( k=0; k<2; k++ ))
do
check_code=$( curl --connect-timeout 3 -sL -w "%{http_code}\\n" http://127.0.0.1:$port -o /dev/null )
if [ "$check_code" != "200" ]; then
count=$(expr $count + 1)
sleep 3
continue
else
count=0
break
fi
done
if [ "$count" != "0" ]; then
#/usr/local/nginx/sbin/nginx -s restart
exit 1
else
exit 0
fi
配置mysql主从切换
配置文件
主配置文件
! Configuration File for keepalived
global_defs {
router_id HA_MySQL #标识，双主相同
}
vrrp_instance VI_1 {
state MASTER
interface ens33
virtual_router_id 51 #分组，主备相同
priority 100 #优先级，这个高一点则先把它作为master
advert_int 1
nopreempt #不主动抢占资源，设置非抢占模式
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.152.131
}
}
virtual_server 192.168.152.131 3306 {
delay_loop 2
lb_algo wrr #带有权重的轮询
lb_kind DR
persistence_timeout 60 #同一IP的连接60秒内被分配到同一台真实服务器
protocol TCP
real_server 192.168.152.132 3306 {
weight 3 #权重为3
notify_down /data/keepalived_shutdown.sh #当mysq服down时，执行此脚本，杀死keepalived实现切换, 自杀脚本.
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
}
从配置文件
! Configuration File for keepalived
global_defs {
router_id HA_MySQL
}
vrrp_instance VI_1 {
state BACKUP
interface ens33
virtual_router_id 51
priority 90 #优先级，这个低一点
advert_int 1
nopreempt
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress { #虚拟IP (VIP)
192.168.152.131
}
}
virtual_server 192.168.152.131 3306 {
delay_loop 2 #每2秒检查一次real_server存活
lb_algo wrr
lb_kind DR
persistence_timeout 60
protocol TCP
real_server 192.168.152.130 3306 {
weight 3
notify_down /data/keepalived_shutdown.sh
TCP_CHECK {
connect_timeout 10 #连接超时时间
nb_get_retry 3 #重连次数
delay_before_retry 3 #重连间隔时间
connect_port 3306 #健康检查端口，配置自己mysql服务端口
}
}
}