集群相关、用keepalived配置高可用集群

1、集群相关

2、keepalived相关

3、用keepalived配置高可用集群

安装：yum install keepalived -y

 

高可用，主要是针对于服务器硬件或服务器上的应用服务而言的，在软件方面就得根据自己的需要而定，这里就针对于nginx服务进行设置
两台电脑都安装上nginx服务

修改keepalived 的配制文件：
vim /etc/keepalived/keepalived.conf
加入：

global_defs {
notification_email {
aming@aminglinux.com
}
notification_email_from root@aminglinux.com
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}

vrrp_script chk_nginx {
script "/usr/local/sbin/check_ng.sh"
interval 3
}

vrrp_instance VI_1 {
state MASTER
interface ens33
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass aminglinux>com
}
virtual_ipaddress {
192.168.188.100
}

track_script {
chk_nginx
}

}

编辑执行脚本文件：
vim /usr/local/sbin/check_ng.sh
加入：

#!/bin/bash
#时间变量，用于记录日志
d=`date --date today +%Y%m%d_%H:%M:%S`
#计算nginx进程数量
n=`ps -C nginx --no-heading|wc -l`
#如果进程为0，则启动nginx，并且再次检测nginx进程数量，
#如果还为0，说明nginx无法启动，此时需要关闭keepalived
if [ $n -eq "0" ]; then
/etc/init.d/nginx start
n2=`ps -C nginx --no-heading|wc -l`
if [ $n2 -eq "0" ]; then
echo "$d nginx down,keepalived will stop" >> /var/log/check_ng.log
systemctl stop keepalived
fi
fi

改变脚本权限：
chmod 755  /usr/local/sbin/check_ng.sh  (增加可执行权限)

然后启动keepalived服务：
systemctl start keepalived 或 service keepalived start
进行查看：ps aux |greep keepalive

查看VIP：

进行测试：

这样子，主的keepalived就设置好了。

配制重服务器keepalived

安装:yum install keepalived -y
修改配制文件：vim /etc/keepalived/keepalived.conf
加入：

global_defs {
notification_email {
aming@aminglinux.com
}
notification_email_from root@aminglinux.com
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}

vrrp_script chk_nginx {
script "/usr/local/sbin/check_ng.sh"
interval 3
}

vrrp_instance VI_1 {
state BACKUP
interface ens33
virtual_router_id 51
priority 90
advert_int 1
authentication {
auth_type PASS
auth_pass aminglinux>com
}
virtual_ipaddress {
192.168.188.100
}

track_script {
chk_nginx
}

}

 

配制检测nginx的脚本：vim /usr/local/sbin/check_ng.sh
加入：

#时间变量，用于记录日志
d=`date --date today +%Y%m%d_%H:%M:%S`
#计算nginx进程数量
n=`ps -C nginx --no-heading|wc -l`
#如果进程为0，则启动nginx，并且再次检测nginx进程数量，
#如果还为0，说明nginx无法启动，此时需要关闭keepalived
if [ $n -eq "0" ]; then
systemctl start nginx      (根据自己的具体情况进行配制相关的服务)
n2=`ps -C nginx --no-heading|wc -l`
if [ $n2 -eq "0" ]; then
echo "$d nginx down,keepalived will stop" >> /var/log/check_ng.log
systemctl stop keepalived
fi
fi

增加执行权限：chmod 755  /usr/local/sbin/check_ng.sh
启动keepalived: systemctl start keepalived
查看：ps aux |grep keepalived

 由于都是外网机器，所以这里暂时无法测试。