上次介绍了一篇nginx+keepalived来实现nginx服务器的高可用，其中的一台nginx是处于闲置的，感觉有点浪费资源，，这次再介绍下nginx+keepalived的nginx双主模式。就是2台nginx同时提供服务，域名解析的时候解析到2个IP上去，有一台挂掉了，所以的请求都会转移到另一台上面去。

之前nginx以及keepalived的安装在这里有介绍： 环境如下： 主nginx服务器:184.173.91.43 备nginx服务器:184.173.91.44 VIP1:184.173.91.47 VIP2:184.173.91.48 nginx和keepalived安装好以后编辑主nginx上面的keepalived.conf

[caoy ~]$ vi /etc/keepalived/keepalived.conf

global_defs { notification_email { linuxcy@126.com } notification_email_from keepalived@localhost.com smtp_server 127.0.0.1 smtp_connect_timeout 30 router_id LVS_DEVEL } vrrp_script chk_http_port { script “/bin/whole51/nginx_pid.sh” interval 2 weight 2 } vrrp_instance VI_1 { state MASTER interface eth1 virtual_router_id 51 priority 100 advert_int 1 authentication { auth_type PASS auth_pass 1111 } track_script { chk_http_port } virtual_ipaddress { 184.173.91.47 } } vrrp_instance VI_2 { state BACKUP interface eth1 virtual_router_id 52 priority 99 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 184.173.91.48 } }

备nginx上面的keepalived.conf文件如下:

[caoy ~]$ vi /etc/keepalived/keepalived.conf

global_defs { notification_email { linuxcy@126.com } notification_email_from keepalived@localhost.com smtp_server 127.0.0.1 smtp_connect_timeout 30 router_id LVS_DEVEL } vrrp_script chk_http_port { script “/bin/whole51/nginx_pid.sh” interval 2 weight 2 } vrrp_instance VI_1 { state BACKUP interface eth1 virtual_router_id 51 priority 99 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 184.173.91.47 } } vrrp_instance VI_2 { state MASTER interface eth1 virtual_router_id 52 priority 100 advert_int 1 authentication { auth_type PASS auth_pass 1111 } track_script { chk_http_port } virtual_ipaddress { 184.173.91.48 } }

然后分别在2台nginx上面添加检测脚本：

[caoy ~]$ vi /bin/whole51/nginx_pid.sh #!/bin/bash A=`ps -C nginx –no-header |wc -l` if [ $A -eq 0 ];then /usr/sbin/nginx sleep 3 if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then killall keepalived fi fi

分别在2台nginx上启动nginx和keepalived服务，然后分别用ip a来查看IP

主nginx(184.173.91.43)的ip [caoy ~]$ /sbin/ip a 3: eth1: mtu 1500 qdisc pfifo_fast qlen 1000 link/ether ae:bb:d0:43:c0:fc brd ff:ff:ff:ff:ff:ffinet 184.173.91.43/27 brd 184.173.91.63 scope global eth1inet 184.173.91.47/32 scope global eth1 inet6 fe80::acbb:d0ff:fe43:c0fc/64 scope link valid_lft forever preferred_lft forever

备nginx(184.173.91.44)的ip

[caoy ~]$ /sbin/ip a 3: eth1: mtu 1500 qdisc pfifo_fast qlen 1000 link/ether f2:3b:4b:db:e5:d7 brd ff:ff:ff:ff:ff:ffinet 184.173.91.44/27 brd 184.173.91.63 scope global eth1inet 184.173.91.48/32 scope global eth1 inet6 fe80::f03b:4bff:fedb:e5d7/64 scope link valid_lft forever preferred_lft forever