nginx与keepalived实现高可用
本实验使用了两台虚拟机
每台都需要安装nginx及keepalived
nginx可以源码安装也可以用yum安装nginx
yum安装nginx需要epel源
一:网络拓扑结构图
二:keepalived及nginx安装
源码安装nginx
[root@localhost ~]#yum -y install pcre-devel zlib-devel make gcc gcc-c++ openssl-devel #安装Nginx依赖包
[root@localhost ~]#useradd -M -s /sbin/nologin nginx #创建一个Nginx测试用户
[root@localhost ~]#tar xf nginx -C /usr/src #将Nginx解包到/usr/src下
[root@localhost ~]#cd /usr/src/nginx
[root@localhost ~]#./configure --prefix=/usr/local/nginx --user=nginx --group=nginx --with-file-aio --with-http_stub_status_module --with-http_gzip_static_module --with-http_flv_module --with-http_ssl_module --with-pcre && make && make install #对Nginx进行编译安装
--prefix 设定Nginx的安装目录
--user和--group 指定Nginx运行用户和组
--with-http_stub_status_module 启用http_stub_status_module模块以支持状态统计
--with-http_ssl_module 启用SSL模块
--with-http_flv_module 启用FLV模块,提供寻求内存使用基于时间的偏移量文件
[root@localhost ~]#ln -s /usr/local/nginx/sbin/nginx /usr/local/bin #给Nginx一个软连接
[root@localhost ~]#nginx -t #检查语法
[root@localhost ~]# nginx #开启Nginx服务
[root@localhost ~]#netstat -lnpt | grep 80 #查看端口
yum安装nginx
#安装nginx
[root@localhost ~]# yum -y install nginx
输入命令:
whereis nginx
即可看到类似于如下的内容:
nginx: /usr/sbin/nginx /usr/lib64/nginx /etc/nginx /usr/share/nginx
以下是Nginx的默认路径:
(1) Nginx配置路径:/etc/nginx/
(2) PID目录:/var/run/nginx.pid
(3) 错误日志:/var/log/nginx/error.log
(4) 访问日志:/var/log/nginx/access.log
(5) 默认站点目录:/usr/share/nginx/html
事实上,只需知道Nginx配置路径,其他路径均可在/etc/nginx/nginx.conf 以及/etc/nginx/conf.d/default.conf 中查询到。
常用命令
(1) 启动:
nginx
(2) 测试Nginx配置是否正确:
nginx -t
(3) 优雅重启:
nginx -s reload
该命令与以下命令类似:
kill -HUP nginx进程号
#安装keepalived
[root@localhost ~]# yum -y install keepalived
三:keepalived配置
主eepalived设置
! Configuration File for keepalived
notification_email {
acassen@firewall.loc
failover@firewall.loc
sysadmin@firewall.loc
}
notification_email_from Alexandre.Cassen@firewall.loc
smtp_server 192.168.200.1
smtp_connect_timeout 30
router_id LVS_DEVEL
vrrp_skip_check_adv_addr
vrrp_strict
vrrp_garp_interval 0
vrrp_gna_interval 0
}
script "/shell/nginx_check.sh"
interval 2
weight -20
}
state MASTER #主
interface eno16777728 #心跳网卡
virtual_router_id 51
priority 100 #优先级
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.200.254
}
track_script {
check_nginx #引用脚本
}
}
[root@localhost ~]# echo "1111111" > /usr/share/nginx/html/index.html
[root@localhost ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
notification_email {
acassen@firewall.loc
failover@firewall.loc
sysadmin@firewall.loc
}
notification_email_from Alexandre.Cassen@firewall.loc
smtp_server 192.168.200.1
smtp_connect_timeout 30
router_id LVS_DEVEL
vrrp_skip_check_adv_addr
vrrp_strict
vrrp_garp_interval 0
vrrp_gna_interval 0
}
script "/shell/nginx_check.sh"
interval 2
weight -20
}
state BACKUP
interface eno16777728
virtual_router_id 51
priority 90
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.200.254
}
track_script {
check_nginx
}
}
[root@localhost ~]# echo "22222" > /usr/share/nginx/html/index.html
四:测试
主服务器工作时
从服务器工作时
五:nginx_check.sh shell文件,配置为周期性任务
count="$(ps -C nginx --no-header|wc -l)"
systemctl restart nginx
sleep 2
if [ ps -c nginx --no-header|wc -l -eq 0 ];then
systemctl stop keepalived
fi
fi