标签：src kconfig rest master span over 负载 can from
（1）准备三台服务器
正常来说，应该准备四台，两台安装ngnix+keeplived实现高可用以及负载均衡，两台做节点服务器，这里78充当一台节点服务器，172.31.113.77（nginx+keepalived），172.31.113.78（nginx+keepalived+tomcat），172.31.113.79（tomcat）。
（2）安装nginx服务器
77，78服务器安装ngnix以及配置负载均衡可以查看之前的博文。
（3）77节点，安装keepalived
1.首先安装keepalived rpm包：popt 以及popt-devel。
2.下载keepalived安装包
cd /usr/local wget http://www.keepalived.org/software/keepalived-1.2.8.tar.gz
3.解压并编译keepalived
tar zvxf /usr/local keepalived-1.2.8.tar.gz cd /usr/local/keepalived-1.2.8 ./configure --prefix=/usr/local/keepalived --sysconf=/etc
执行编辑的时候会报如下Openssl错误：
configure: error: !!! OpenSSL is not properly installed on your system. !!! !!! Can not include OpenSSL headers files. !!!
解决方案：http://kusix.iteye.com/blog/1226892
4.编译并安装
make && make install
5.启动keepalived
cp /usr/local/keepalived/sbin/keepalived /bin/ chkconfig --add keepalived #设置开机启动 chkconfig keepalived on #启动keepalive服务 /etc/init.d/keepalived start
（4）配置keepalived
cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf_bak
vim /etc/keepalived/keepalived.conf
（1）配置MASTER节点
global_defs { 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_script Monitor_Nginx { script "/root/monitor_nginx.sh" #执行脚本路径 interval 2 weight 2 } vrrp_instance VI_1 { state MASTER #标识为MASTER节点，从节点标识BACKUP interface eth0 virtual_router_id 51 #两个节点的ID需要一致 priority 100 #主、备机取不同的优先级，主机值较大，备份机值较小,值越大优先级越高 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 172.31.113.110 #虚拟IP } track_script { Monitor_Nginx #执行脚本名字 } }
（2）编辑监控脚本monitor_nginx.sh，vim /root/monitor_nginx.sh，内容如下，并赋予执行权限：chmod +x /root/monitor_nginx.sh
#!/bin/bash counter=$(ps -C nginx --no-heading|wc -l) if [ "${counter}" = "0" ]; then # /usr/local/nginx/sbin/nginx # sleep 2 # counter=$(ps -C nginx --no-heading|wc -l) # if [ "${counter}" = "0" ]; then /etc/init.d/keepalived stop # fi fi
到此，keepalived的安装以及配置结束，78备用节点重复上面的操作，只是把配置文件keepalived.conf中的state修改为BACKUP , priority比MASTER稍低即可。
（5）分别启动keepalived，nginx，以及tomcat服务器。
service keepalived restart
在主服务器即78节点，可以通过 ip a查看虚拟IP，显示如下：
（6）测试nginx+keepalive实现高可用
访问172.31.113.110/index.jsp，首先将77服务器的nginx进程杀掉，查看77的keepalived进行也被停止掉了（因为上面我们的脚本当nginx为零的时候，停止keepalived，只有停止keepalived，78备用服务器才能得到虚拟IP），这时候查看78的虚拟IP也为172.31.113.110，继续对外提供服务。
总结：这种方案只能实现当主节点的nginx进程结束了，主节点的脚本monitor_nginx.sh执行后，停止keepalived进程，备用节点才能得到虚拟IP，进而对外继续提供服务。后面测试了一下，直接关闭主节点，备用节点无法得到虚拟IP，无法对外服务。所以当主节点直接宕机的话，这种方案就不可行了，难道这种方案就是高可用？百度搜了好久，都是这样实现的。
标签：src kconfig rest master span over 负载 can from
原文地址：http://www.cnblogs.com/gdpuzxs/p/7517742.html
