使用keepalived+nginx+tomcat搭建高性能web服務器集群，系統采用centos6.9，前端用nginx做反向代理實現負載均衡，同時結合keepalived對nginx實現高可用，後端使用兩臺tomcat做動態jsp解析，實現了動靜分離。

搭建環境

準備四臺服務器
vip: 192.168.75.130
master: 192.168.75.131 (安裝nginx做反向代理實現負載勻衡，結合keepalived實現高可用）
backup: 192.168.75.132 (同上)
web1: 192.168.75.151 (安裝nginx和tomcat實現動靜分離)
web2: 192.168.75.152 (同上)
這裏為節省服器，nginx和tomcat和裝在了一臺服務上，也可以分開配置。

配置步驟如下：

四臺服務器分別安裝好nginx
安裝方法參見：LNMP環境搭建

web1，web2上分別安裝好tomcat

安裝方法參見：Tomcat8.5的安裝配置

web1, web2上分別啟動nginx和tomcat
service nginx start
service tomcat start

在master和backup上配置nginx：

vi /usr/local/nginx/conf/nginx.conf

加入或修改以下內容：

upstream web_nginx {
#ip_hash;
server 192.168.75.151;
server 192.168.75.152;
}

upstream web_tomcat {
server 192.168.75.151:8080;
server 192.168.75.152:8080;

server {
listen 80;
server_name localhost;

#charset koi8-r;

#access_log logs/host.access.log main;

location / {
proxy_pass http://web_nginx/;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

location ~ \.jsp$ {
proxy_pass http://web_tomcat;
}

分別在master和backup上啟動nginx服務

service nginx start

在master和backup上分別安裝keepalived
yum install -y keepalived

配置master
vi /etc/keepalived/keepalived.conf
清空原文，加入如下內容：
! Configuration File for keepalived

global_defs {
notification_email {
[email protected]
[email protected]
[email protected]
}
#notification_email_from [email protected]
#smtp_server 192.168.200.1
#smtp_connect_timeout 30
router_id LVS_DEVEL
}

vrrp_script chk_http_port {
script "</dev/tcp/127.0.0.1/80"
interval 1
weight -2
}

vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.75.130
}
track_script {
chk_http_port
}
}

配置backup
scp 192.168.75.131:/etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf

vi /etc/keepalived/keepalived.conf
backup的配置文件只需要修改
state MASTER -> state BACKUP
priority 100 -> priority 99

最後，分別在master和backup上啟動keepalived服務，先主後備
/etc/init.d/keepalived start

keepalived+nginx+tomcat搭建高性能web服務器集群