怎么在keepalived中使用nginx实现高可用

这期内容当中小编将会给大家带来有关怎么在keepalived中使用nginx实现高可用，文章内容丰富且以专业的角度为大家分析和叙述，阅读完这篇文章希望大家可以有所收获。

1.keepalived介绍

keepalived最初是专为LVS负载均衡软件设计的，用来管理并监控LVS集群系统中各个服务节点的状态，后来又加入了实现高可用的VRRP功能。keepalived除了能够管理LVS软件外，还能支持其他服务的高可用解决方案。

keepalived通过VRRP协议实现高可用功能的。VRRP（Virtual Router Redundancy Protocol）虚拟路由冗余协议。VRRP出现的目的就是为了解决静态路由单点故障问题，它能保证当个别节点宕机时，整个网络可以不间断地运行。

2.keepalived高可用故障转移原理

keepalived高可用服务之间的故障转移，是通过VRRP来实现的。在keepalived服务工作时，主Master节点会不断地向备节点发送（多播的方式）心跳消息，用来告诉备Backup节点自己还活着。

　　当主节点发生故障时，无法给备节点发送心跳消息，如果备节点无法继续检测到来自主节点的心跳。就会调用自身的接管程序，接管主节点的IP资源和服务。当主节点恢复时，备节点又会释放主节点故障时自身接管的IP资源和服务，恢复到原来的备用角色

3.安装nginx

3.1.主节点（192.168.80.22）

3.1.1.安装编译工具和库文件

yum -y install make zlib zlib-devel gcc-c++ libtool openssl openssl-devel

3.1.2.安装pcre

#进入目录cd /usr/local/develop/anginx#上传安装文件并解压tar -zxvf pcre-8.38.tar.gz#进入安装目录cd pcre-8.38#检查配置./configure#编译、安装make && make install#查看pcre版本pcre-config --version

3.1.3.安装nginx

#进入目录cd /usr/local/develop/anginx#上传安装文件，并解压tar -zxvf nginx-1.8.1.tar.gz#进入安装目录cd nginx-1.8.1#检查配置./configure --prefix=/usr/local/develop/anginx/webserver/nginx --with-http_stub_status_module --with-http_ssl_module --with-pcre=/usr/local/develop/anginx/pcre-8.38#编译安装make && make install#查看nginx版本 /usr/local/develop/anginx/webserver/nginx/sbin/nginx -v--------------------------------------------------------[root@hadoop02 webserver]# /usr/local/develop/anginx/webserver/nginx/sbin/nginx -vnginx version: nginx/1.8.1#配置nginx（检查）/usr/local/develop/anginx/webserver/nginx/sbin/nginx -t#nginx管理命令/usr/local/develop/anginx/webserver/nginx/sbin/nginx       # 启动 Nginx/usr/local/develop/anginx/webserver/nginx/sbin/nginx -s stop       # 停止 Nginx/usr/local/develop/anginx/webserver/nginx/sbin/nginx -s reload      # 重新载入配置文件/usr/local/develop/anginx/webserver/nginx/sbin/nginx -s reopen      # 重启 Nginx

3.1.4.nginx基础配置

vi nginx.conf#user nobody;worker_processes 1;#error_log logs/error.log;#error_log logs/error.log notice;#error_log logs/error.log info;pid    logs/nginx.pid;events {  worker_connections 1024;}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"';  access_log logs/access.log main;  sendfile    on;  #tcp_nopush   on;  #keepalive_timeout 0;  keepalive_timeout 65;  #gzip on;    #添加tomcat列表，真实应用服务器都放在这  upstream tomcat_pool{    #server tomcat地址:端口号 weight表示权值，权值越大，被分配的几率越大;    server 192.168.80.22:8080 weight=4 max_fails=2 fail_timeout=30s;    server 192.168.80.22:8081 weight=4 max_fails=2 fail_timeout=30s;      }  server {    listen    80;    server_name tomcat_pool;    #charset koi8-r;    #access_log logs/host.access.log main;    location / {      #root  html;      #index index.html index.htm;      proxy_pass http://tomcat_pool;  #转向tomcat处理      proxy_set_header  Host       $host;      proxy_set_header  X-Real-IP    $remote_addr;      proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;    }    #error_page 404       /404.html;    # redirect server error pages to the static page /50x.html    #    error_page  500 502 503 504 /50x.html;    location = /50x.html {      root  html;    }}

3.2.备节点（192.168.80.21）

说明：安装方式同nginx主节点。

4.安装keepalived

4.1.主节点（192.168.80.22）

#安装keepalivedyum install keepalived -y#启动keepalived服务/etc/init.d/keepalived start-------------------------------------------[root@hadoop02 anginx]# /etc/init.d/keepalived start正在启动 keepalived：                   [确定][root@hadoop02 anginx]# ps -ef |grep keepalivedroot   15723   1 0 00:59 ?    00:00:00 /usr/sbin/keepalived -Droot   15724 15723 0 00:59 ?    00:00:00 /usr/sbin/keepalived -Droot   15725 15723 0 00:59 ?    00:00:00 /usr/sbin/keepalived -Droot   15731 15622 0 00:59 pts/1  00:00:00 grep keepalived[root@hadoop02 anginx]##设置开机自启动echo "/etc/init.d/keepalived start" >>/etc/rc.local#关闭keepalived服务/etc/init.d/keepalived stop#编辑keepalived配置文件vi /etc/keepalived/keepalived.conf-----------------------------------------------------------! Configuration File for keepalivedglobal_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 lb01}vrrp_instance VI_1 {  state MASTER  interface eth2  virtual_router_id 55  priority 150  advert_int 1  authentication {    auth_type PASS    auth_pass server123  }  virtual_ipaddress {    192.168.80.100 dev eth2 label eth2:1  }}...........................................................

关于配置说明：

• 【router_id】 是路由标识，在一个局域网里面应该是唯一的

• 【vrrp_instance VI_1】{...}这是一个VRRP实例，里面定义了keepalived的主备状态、接口、优先级、认证和IP信息

• 【state】 定义了VRRP的角色

• 【interface】定义使用的接口，这里我的服务器用的网卡都是eth2

• 【virtual_router_id】是虚拟路由ID标识，一组的keepalived配置中主备都是设置一致

• 【priority】是优先级，数字越大，优先级越大，

• 【auth_type】是认证方式

• 【auth_pass】是认证的密码

• 【virtual_ipaddress】 ｛...｝定义虚拟IP地址，可以配置多个IP地址，这里我定义为192.168.80.100，绑定了eth2的网络接口，虚拟接口eth2:1

4.2.备节点（192.168.80.21）

#安装keepalivedyum install keepalived -y#启动keepalived服务/etc/init.d/keepalived start-------------------------------------------[root@hadoop02 anginx]# /etc/init.d/keepalived start正在启动 keepalived：                   [确定][root@hadoop02 anginx]# ps -ef |grep keepalivedroot   15723   1 0 00:59 ?    00:00:00 /usr/sbin/keepalived -Droot   15724 15723 0 00:59 ?    00:00:00 /usr/sbin/keepalived -Droot   15725 15723 0 00:59 ?    00:00:00 /usr/sbin/keepalived -Droot   15731 15622 0 00:59 pts/1  00:00:00 grep keepalived[root@hadoop02 anginx]##设置开机自启动echo "/etc/init.d/keepalived start" >>/etc/rc.local#关闭keepalived服务/etc/init.d/keepalived stop#编辑keepalived配置文件vi /etc/keepalived/keepalived.conf-----------------------------------------------------------------! Configuration File for keepalivedglobal_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 lb02}vrrp_instance VI_1 {  state BACKUP  interface eth2  virtual_router_id 55  priority 100  advert_int 1  authentication {    auth_type PASS    auth_pass server123  }  virtual_ipaddress {    192.168.80.100 dev eth2 label eth2:1  }}.............................................................

5.测试

5.1.启动主备节点的keepalived服务

#在节点一执行（192.168.80.22）/etc/init.d/keepalived start-------------------------------------[root@hadoop02 anginx]# ps -ef |grep keepalivedroot   15788   1 0 01:09 ?    00:00:00 /usr/sbin/keepalived -Droot   15790 15788 0 01:09 ?    00:00:00 /usr/sbin/keepalived -Droot   15791 15788 0 01:09 ?    00:00:00 /usr/sbin/keepalived -Droot   15807 15622 0 01:33 pts/1  00:00:00 grep keepalived[root@hadoop02 anginx]##在节点二执行（192.168.80.21）/etc/init.d/keepalived start---------------------------------------[root@hadoop01 ~]# ps -ef |grep keepalivedroot   11542   1 0 01:30 ?    00:00:00 /usr/sbin/keepalived -Droot   11544 11542 0 01:30 ?    00:00:00 /usr/sbin/keepalived -Droot   11545 11542 0 01:30 ?    00:00:00 /usr/sbin/keepalived -Droot   11550 11512 0 01:33 pts/1  00:00:00 grep keepalived[root@hadoop01 ~]#

5.2.通过虚ip访问服务

http://192.168.80.100/session-redis-demo/

5.3.停止主节点keepalived服务

#在节点一执行（192.168.80.22）/etc/init.d/keepalived stop#观察备节点变化ip addr-------------------------------------------[root@hadoop01 ~]# ip addr1: lo:  mtu 65536 qdisc noqueue state UNKNOWN   link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00  inet 127.0.0.1/8 scope host lo  inet6 ::1/128 scope host     valid_lft forever preferred_lft forever2: eth2:  mtu 1500 qdisc pfifo_fast state UP qlen 1000  link/ether 00:50:56:38:e5:46 brd ff:ff:ff:ff:ff:ff  inet 192.168.80.21/24 brd 192.168.80.255 scope global eth2  inet 192.168.80.100/32 scope global eth2:1  inet6 fe80::250:56ff:fe38:e546/64 scope link     valid_lft forever preferred_lft forever[root@hadoop01 ~]#

5.4.继续通过虚ip访问服务

http://192.168.80.100/session-redis-demo/

6.keepalived+nginx整合

说明：编写nginx守护脚本，如果nginx服务出现故障，则停止当前节点的keepalived服务。自动切换到备用节点。

6.1.编写nginx守护脚本

vi nginx_check.sh--------------------------------------#!/bin/bashwhile truedoif [ $(netstat -tlnp|grep nginx|wc -l) -ne 1 ]then  /etc/init.d/keepalived stopfisleep 2done#给脚本授权chmod u+x nginx_check.sh#执行脚本nohup /usr/local/develop/anginx/shell/nginx_check.sh &

6.2.停止主节点nginx服务

#停止主节点nginx服务/usr/local/develop/anginx/webserver/nginx/sbin/nginx -s stop#查找进程[root@hadoop02 ~]# ps -ef |grep nginxroot   15915   1 0 01:51 ?    00:00:00 /bin/bash /usr/local/develop/anginx/shell/nginx_check.shroot   16516 15753 0 01:54 pts/5  00:00:00 grep nginx[root@hadoop02 ~]##观察备用节点变化【服务正常】ip addr--------------------------------------[root@hadoop01 shell]# ip addr1: lo:  mtu 65536 qdisc noqueue state UNKNOWN   link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00  inet 127.0.0.1/8 scope host lo  inet6 ::1/128 scope host     valid_lft forever preferred_lft forever2: eth2:  mtu 1500 qdisc pfifo_fast state UP qlen 1000  link/ether 00:50:56:38:e5:46 brd ff:ff:ff:ff:ff:ff  inet 192.168.80.21/24 brd 192.168.80.255 scope global eth2  inet 192.168.80.100/32 scope global eth2:1  inet6 fe80::250:56ff:fe38:e546/64 scope link     valid_lft forever preferred_lft forever[root@hadoop01 shell]##再次重新启动主节点nginx和keepalived服务/usr/local/develop/anginx/webserver/nginx/sbin/nginx/etc/init.d/keepalived start

上述就是小编为大家分享的怎么在keepalived中使用nginx实现高可用了，如果刚好有类似的疑惑，不妨参照上述分析进行理解。如果想知道更多相关知识，欢迎关注行业资讯频道。