nginx+keepalived实现负载均衡

sadw

环境需求：
hostname：web1    ip：192.168.1.241
hostname：ha1     ip：192.168.1.243
hostname：ha2     ip：192.168.1.242
keepalived        vip：192.168.1.245

1.nginx+upstream安装（ha1和ha2配置一样）
[iyunv@ha1 opt]# yum -y install gcc gcc-c++ openssl openssl-devel
[iyunv@ha1 opt]# useradd nginx -s /sbin/nologin
[iyunv@ha1 opt]# tar zxf pcre-8.34.tar.gz
[iyunv@ha1 opt]# cd pcre-8.34
[iyunv@ha1 pcre-8.34]# ./configure
[iyunv@ha1 pcre-8.34]# make && make install
[iyunv@ha1 opt]# tar zxf tengine-1.5.1.tar.gz
[iyunv@ha1 opt]# cd tengine-1.5.1
[iyunv@ha1 tengine-1.5.1]# ./configure --user=nginx --group=nginx --prefix=/usr/local/nginx --with-http_stub_status_module --with-http_ssl_module
[iyunv@ha1 tengine-1.5.1]# make && make install

[iyunv@ha1 ~]# mv /usr/local/nginx/conf/nginx.conf /usr/local/nginx/conf/nginx.conf.bak
[iyunv@ha1 ~]# vi /usr/local/nginx/conf/nginx.conf（新建nginx配置文件）
添加一下配置
user nginx nginx;
worker_processes auto;
worker_rlimit_nofile 65535;
error_log /var/log/www/error.log;
#pid      logs/nginx.pid;
events {
    use epoll;
    worker_connections  51200;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
  log_format  main  '$remote_addr - $remote_user [$time_local] "$request"'
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';


    server_info  off;
    server_tag   off;
    server_name_in_redirect off;
    access_log  /var/log/www/access.log  main;
    client_max_body_size 20m;
    client_header_buffer_size 16k;
    large_client_header_buffers 4 16k;
    sendfile        on;
    tcp_nopush     on;
    keepalive_timeout  65;
    server_tokens on;
    gzip  on;
    gzip_min_length 1k;
    gzip_buffers 4 16k;
    gzip_proxied   any;
    gzip_http_version 1.1;
    gzip_comp_level 3;
    gzip_types text/plain application/x-javascript text/css application/xml;
    gzip_vary on;
    upstream kim {
consistent_hash $request_uri;
       server 192.168.1.241:80;
check interval=3000 rise=2 fall=5 timeout=1000 type=http;
        check_http_send "GET / HTTP/1.0\r\n\r\n";
        check_http_expect_alive http_2xx http_3xx;
    }
    server {
        listen       80;
        server_name  localhost;
        location / {
        proxy_next_upstream error timeout invalid_header http_500 http_503 http_404 http_502 http_504;
        proxy_pass http://kim;
        proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
    }
    }

[iyunv@ha1 conf]# vi /etc/init.d/nginxd（新建nginx启动文件）
添加以下配置
#! /bin/sh
# chkconfig: 2345 55 25
# Description: Startup script for nginx webserver on Debian. Place in /etc/init.d and
# run 'update-rc.d -f nginx defaults', or use the appropriate command on your
# distro. For CentOS/Redhat run: 'chkconfig --add nginx'

### BEGIN INIT INFO
# Provides:          nginx
# Required-Start:    $all
# Required-Stop:     $all
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: starts the nginx web server
# Description:       starts nginx using start-stop-daemon
### END INIT INFO

PATH=/usr/local/nginx/sbin:/usr/local/nginx/bin:/sbin:/bin:/usr/sbin:/usr/bin
DESC="nginx daemon"
NAME=nginx
DAEMON=/usr/local/nginx/sbin/$NAME
CONFIGFILE=/usr/local/nginx//conf/$NAME.conf
PIDFILE=/usr/local/nginx//logs/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME

set -e
[ -x "$DAEMON" ] || exit 0

do_start() {
$DAEMON -c $CONFIGFILE || echo -n "nginx already running"
}

do_stop() {
kill -INT `cat $PIDFILE` || echo -n "nginx not running"
}

do_reload() {
kill -HUP `cat $PIDFILE` || echo -n "nginx can't reload"
}

case "$1" in
start)
echo -n "Starting $DESC: $NAME"
do_start
echo "."
;;
stop)
echo -n "Stopping $DESC: $NAME"
do_stop
echo "."
;;
reload|graceful)
echo -n "Reloading $DESC configuration..."
do_reload
echo "."
;;
restart)
echo -n "Restarting $DESC: $NAME"
do_stop
do_start
echo "."
;;
*)
echo "Usage: $SCRIPTNAME {start|stop|reload|restart}" >&2
exit 3
;;
esac

exit 0

[iyunv@ha1 keepalived]# chmod o+x /etc/init.d/nginxd  （赋予执行权限）
[iyunv@ha1 keepalived]# /etc/init.d/nginxd start
2.测试nginx
（1）测试web1正常访问

（3）测试ha1负载web1

（3）测试ha2负载web1

3.安装keepalived（ha1与ha2一样配置）
[iyunv@ha1 ~]# yum -y install keepalived （要保证ha1与ha2上的keepalived版本一致）
[iyunv@ha1 ~]# mkdir /etc/keepalived/script （新建nginx检车脚本存放目录）
[iyunv@ha1 ~]# vi /etc/keepalived/script/check_nginx.sh  （新建nginx检测脚本）
添加以下内容
!/bin/sh
# check nginx server status
NGINX=/usr/local/nginx/sbin/nginx
PORT=80

nmap localhost -p $PORT | grep "$PORT/tcp open"
#echo $?
if [ $? -ne 0 ];then
    $NGINX -s stop
    sleep 3
    nmap localhost -p $PORT | grep "$PORT/tcp open"
    [ $? -ne 0 ] && /etc/init.d/keepalived stop
fi

[iyunv@ha1 ~]# chmod o+x /etc/keepalived/script/check_nginx.sh （赋予执行权限）
（1）新建keepalived配置文件（在ha1上配置）
[iyunv@ha1 ~]# mv /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak
[iyunv@ha1 ~]# vi /etc/keepalived/keepalived.conf
添加以下配置
! Configuration File for keepalived
global_defs {
   notification_email {
    root@localhost
}
   notification_email_from kim@163.com
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
}
vrrp_script chk_http_port {
    script "/etc/keepalived/script/check_nginx.sh"
    interval 2
    weight 2
}
vrrp_instance VI_1 {
    state MASTER
    interface eth1
    virtual_router_id 56
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1234
    }
track_script {
    chk_http_port
}
    virtual_ipaddress {
    192.168.1.245
    }
}

（2）新建keepalived配置文件（在ha2上配置）
[iyunv@ha2 ~]# mv /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak
[iyunv@ha2 ~]# vi /etc/keepalived/keepalived.conf
添加以下配置
! Configuration File for keepalived
global_defs {
   notification_email {
    root@localhost
}
   notification_email_from kim@163.com
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
}
vrrp_script chk_http_port {
    script "/etc/keepalived/script/check_nginx.sh"
    interval 2
    weight 2
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth1
    virtual_router_id 56
    priority 99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1234
    }
track_script {
    chk_http_port
}
    virtual_ipaddress {
    192.168.1.245
    }
}

4.测试keepalived



以上可以看出虚拟ip在ha1上


以上可以看出，nginx断开后，虚拟ip漂移到ha2上

由上图可见，利用vip访问，负载正常