Nginx负载均衡器+Keepalvied双机互备+tomcat集群

Nginx负载均衡器+Keepalvied双机互备+tomcat集群 http://doc.guandang.net/chenshengang/blog/item/9dc9beb5ce83a8798ad4b24a.html

Nginx作负载均衡器的优点许多，简单概括为:①实现了可弹性化的架构，在压力增大的时候可以临时添加tomcat服务器添加到这个架构里面去;②upstream具有负载均衡能力，可以自动判断下面的机器，并且自动踢出不能正常提供服务的机器；而Keepalvied可保证单个nginx负载均衡器的有效性，避免单点故障，整个拓补如下：

nginx(主负载均衡器)：192.168.1.106

nginx(从负载均衡器)：192.168.1.107

VIP地址: 192.168.1.108

tomcat1的IP 192.168.1.102

tomcat2的IP 192.168.1.103

tomcat3的IP 192.168.1.105

布置整个环境用到的软件为:

apache-tomcat-6.0.20.tar.gz

jdk-6u16-linux-i586.bin

nginx-0.7.17.tar.gz

prce-7.7.tar.gz

①首先分别在3台tomcat主机上布置java环境，安装tomcat，具体步骤为：

apache-tomcat-6.0.tar.gz可在http://doc.guandang.net上下载，

jdk-6u16-linux-i586.bin我是用文件挖掘者直接搜索下载的

第一步，安装java环境。

JDK的安装

#chmod +x jdk-6u16-linux-i586.bin

#./jdk-6u16-linux-i586.bin

到此JDK已经安装完成

建立符号链接

# ln -s /usr/local/jdk-1.6.0-16/bin/java /usr/bin/java

# ln -s /usr/local/jdk-1.6.0-16/bin/javac /usr/bin/javac

ln -s /usr/local/jdk-1.6.0-16 /usr/local/jdk

ln -s /usr/local/jdk-1.6.0-16/jre /usr/local/jre

TOMCAT的安装

#tar zxvf apache-tomcat-6.0.20.tar.gz

#mv apache-tomcat-6.0.20 /usr/local/tomcat

设置环境变量: vim /etc/rc.d/rc.local，以追加的形式添加如下内容 JAVA_HOME=/usr/local/jdk

export JAVA_HOME

JRE_HOME=/usr/local/jre

export JRE_HOME

CLASSPATH=/usr/local/tomcat/common/lib/:/usr/local/jdk/lib:/usr/local/jre/lib

export CLASSPATH

PATH=$PATH:/usr/local/tomcat/bin/:/usr/local/apache/bin:/usr/local/jdk/bin:/usr/local/jre/bin

export PATH

TOMCAT_HOME=/usr/local/tomcat

export TOMCAT_HOME

重启服务器，启动tomcat以检查是否存在错误：

#cd /usr/local/tomcat/bin

#./startup.sh :8080 可以看到猫头:)成功了。

②分别在二台nginx负载均衡器上安装nginx及配置

下载及安装nginx:

tar zxvf pcre-7.7.tar.gz

cd pcre-7.7/

./configure

make && make install

tar zxvf nginx-0.7.17.tar.gz

cd nginx-0.7.17/

./configure --prefix=/usr/local/nginx --with-http_stub_status_module make && make install

这里贴上nginx.conf配置文件，不加任何说明，方便用X-shell直接粘贴，很人性化的噢:)二个nginx负载均衡器的文件一样，配置完成后分别用/usr/local/nginx/sbin/nginx启动。 user nobody nobody;

worker_processes 1;

pid /usr/local/nginx/logs/nginx.pid;

worker_rlimit_nofile 51200;

events

{

use epoll;

worker_connections 51200;

}

http{

include mime.types;

default_type application/octet-stream;

server_names_hash_bucket_size 128;

client_header_buffer_size 32k;

large_client_header_buffers 4 32k;

client_max_body_size 8m;

sendfile on;

tcp_nopush on;

keepalive_timeout 60;

tcp_nodelay on;

fastcgi_connect_timeout 300;

fastcgi_send_timeout 300;

fastcgi_read_timeout 300;

fastcgi_buffer_size 64k;

fastcgi_buffers 4 64k;

fastcgi_busy_buffers_size 128k;

fastcgi_temp_file_write_size 128k;

gzip on;

gzip_min_length 1k;

gzip_buffers 4 16k; gzip_http_version 1.0;

gzip_comp_level 2;

gzip_types text/plain application/x-javascript text/css

application/xml;

gzip_vary on;

upstream backend

{

server 192.168.1.102:8080;

server 192.168.1.103:8080;

server 192.168.1.105:8080;

}

server {

listen 80;

location / {

root /var/www ;

index index.jsp index.htm index.html;

proxy_redirect off;

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 /nginx {

#access_log on;

#auth_basic "NginxStatus";

#auth_basic_user_file /usr/local/nginx/htpasswd;

#}

log_format access '$remote_addr - $remote_user [$time_local] "$request" '

'$status $body_bytes_sent "$http_referer" '

'"$http_user_agent" $http_x_forwarded_for';

access_log /var/log/access.log access;

}

}

③在二台Nginx机上安装及配置keepalived，做双机互备。

#tar zxvf keepalived-1.1.15.tar.gz

#cd keepalived-1.1.15

#./configure

#make

#make install

将keepalived做成启动脚务，方便管理:

#cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/

#cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/

#mkdir /etc/keepalived

#cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/ #cp /usr/local/sbin/keepalived /usr/sbin/

#service keepalived start|stop

在二台Nginx上，我分别贴出keepalived.conf配置文件，配置完成后分别用service keepalived start启动。检验keepalived是否成功可用命令ip a vrrp_instance VI_INET1 {

state MASTER

interface eth0

virtual_router_id 53

priority 200

advert_int 1

authentication {

auth_type pass

auth_pass yourpass

}

virtual_ipaddress {

192.168.1.108

}

}

vrrp_instance VI_INET1 {

state BACKUP

interface eth0

virtual_router_id 53

priority 100

advert_int 1

authentication {

auth_type pass

auth_pass yourpass

}

virtual_ipaddress {

192.168.1.108

}

}

以上三步完成后，就是检测了，大家可任意停掉其中一台的任何服务；在正常结果中大家应该发现，其中任意一台服务器宕机后，不影响整个系统的运作。