1、本文的架构图:
阐述各服务器用途:
1、haproxy在本构架中实现的是:负载均衡
2、keepalived实现对haproxy的高可用
3、apache static 实现静态页面的访问
4、aoache dynamic实现动态页面的访问,图中有两个是实现负载均衡的
配置各功能模块:
一、配置haproxy和keepalived
验证:
1、当一台keepalived宕机后,VIP会不会转移到另外一台服务器
2、当一台haproxy服务出故障,VIP会不会转移到另外一台服务器
注意:
那如果keepalived宕机了,haproxy服务还正常运行,我们要不要让另外一台服务器把VIP夺过去呢?
理论上来讲:最好不要,但是我们的keepalived中的脚本监控着haproxy的进程,keepalived宕机之后,就无从得知haproxy的健康状态,也不能决定自己的优先权priority降不降低了。所以,理论上来讲最好不要,但是实际中光靠keepalived是做不到的。
配置:
1、给两台服务器分别安装上keepalived
1 | [root@station139 ~]# yum -y install keepalived |
2、配置keepalived
[root@node2 ~]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { notification_email { root@localhost 配置服务状态变化发送邮件到哪个地址 } notification_email_from kaadmin@localhost smtp_server 127.0.0.1 给哪个smtp服务器发邮件 smtp_connect_timeout 30 联系上面smtp服务器30秒联系不上,就超时 router_id LVS_DEVEL } vrrp_script chk_haproxy { 本脚本是用来检测该服务器上haproxy服务的健康状态的 script "killall -0 haproxy" interval 1 weight -2 } vrrp_instance VI_1 { state MASTER 这太服务器为主的keepalived interface eth0 通过eth0网卡广播 virtual_router_id 200 虚拟路由id要改,如果在一个局域网中有多个keepalived集群 priority 100 优先级 advert_int 1 authentication { auth_type PASS auth_pass 11112222 } track_script { chk_haproxy } virtual_ipaddress { 192.168.1.200 本机的虚拟IP } notify_master "/etc/keepalived/notify.sh master" 各不用状态下运行的脚本 notify_backup "/etc/keepalived/notify.sh backup" notify_fault "/etc/keepalived/notify.sh fault" } vrrp_instance VI_2 { 另外一台主keepalived的从 state BACKUP interface eth0 virtual_router_id 57 priority 99 设置要比另外一台主keepalived的优先级低 advert_int 1 authentication { auth_type PASS auth_pass 1111 } track_script { chk_mantaince_down } virtual_ipaddress { 192.168.1.201 } }
3、写keepalived处在不同状态下所运行的脚本
#!/bin/bash # Author: MageEdu <linuxedu@foxmail.com> # description: An example of notify script # vip=192.168.1.200 contact='root@localhost' notify() { mailsubject="`hostname` to be $1: $vip floating" mailbody="`date '+%F %H:%M:%S'`: vrrp transition, `hostname` changed to be $1" echo $mailbody | mail -s "$mailsubject" $contact } case "$1" in master) notify master /etc/rc.d/init.d/haproxy start exit 0 ;; backup) notify backup /etc/rc.d/init.d/haproxy stop exit 0 ;; fault) notify fault /etc/rc.d/init.d/haproxy stop exit 0 ;; *) echo 'Usage: `basename $0` {master|backup|fault}' exit 1 ;; esac 给脚本以执行权限: chmod +x /etc/keepalived/notify.sh
4、配置haproxy
因为要实现动静分离,那么我们在配置文件中,就要定义动态资源静态资源转移到不同的服务上去
[root@node2 ~]# yum -y install haproxy 安装haproxy [root@node2 ~]# vim /etc/haproxy/haproxy.cfg # log 127.0.0.1 local2 chroot /var/lib/haproxy pidfile /var/run/haproxy.pid maxconn 4000 user haproxy group haproxy daemon # turn on stats unix socket stats socket /var/lib/haproxy/stats #--------------------------------------------------------------------- # common defaults that all the 'listen' and 'backend' sections will # use if not designated in their block #--------------------------------------------------------------------- defaults mode http 指定haproxy工作模式为http log global option httplog option dontlognull option http-server-close 当客户端超时时,允许服务端断开连接 option forwardfor except 127.0.0.0/8 在http的响应头部加入forwardfor option redispatch #在使用了基于cookie的会话保持的时候,通常加这么一项,一旦后端某一server宕机时,能够将其会话重新派发到其它的upstream servers retries 3 timeout http-request 10s timeout queue 1m timeout connect 10s timeout client 1m timeout server 1m timeout http-keep-alive 10s timeout check 10s maxconn 3000 #--------------------------------------------------------------------- # main frontend which proxys to the backends #--------------------------------------------------------------------- frontend main *:80 前端代理 acl url_static path_beg -i /static /p_w_picpaths /javascript /stylesheets acl url_static path_end -i .jpg .gif .png .css .js acl url_dynamic path_end -i .php use_backend static if url_static default_backend dynamic #--------------------------------------------------------------------- # static backend for serving up p_w_picpaths, stylesheets and such #--------------------------------------------------------------------- backend static 后端的静态请求响应 balance roundrobin server static 192.168.1.100:80 inter 3000 rise 2 fall 3 check maxconn 5000 #--------------------------------------------------------------------- # round robin balancing between the various backends #--------------------------------------------------------------------- backend dynamic 后端的动态请求响应 balance roundrobin server dynamic1 192.168.1.101:80 inter 3000 rise 2 fall 3 check maxconn 5000 server dynamic2 192.168.1.102:80 inter 3000 rise 2 fall 3 check maxconn 5000 listen statistics mode http bind *:8080 ~ stats enable stats auth admin:admin stats uri /admin?stats 指定URI的访问路径 stats admin if TRUE stats hide-version stats refresh 5s acl allow src 192.168.0.0/24 定义访问控制列表 tcp-request content accept if allow tcp-request content reject
5、配置另外一台haproxy服务器
因为两台服务器的配置大体相同,我们就直接讲以上配置好的复制文件和脚本文件都传到这台haproxy服务器上,做下修就可以了
[root@node2 ~]# scp /etc/keepalived/keepalived.conf root@192.168.1.121:/etc/keepalived/ root@192.168.1.121's password: keepalived.conf 100% 4546 4.4KB/s 00:00 [root@node2 ~]# scp /etc/keepalived/notify.sh root@192.168.1.121:/etc/keepalived/ root@192.168.1.121's password: notify.sh 100% 751 0.7KB/s 00:00 [root@node2 ~]# scp /etc/haproxy/haproxy.cfg root@192.168.1.121:/etc/haproxy/ root@192.168.1.121's password: haproxy.cfg 100% 3529 3.5KB/s 00:00
传输完成,接着来配置 /etc/keepalived/keepalived.conf 因为两个节点上的/etc/haproxy/haproxy.cfg相同不用更改
interface eth0 ! Configuration File for keepalived global_defs { notification_email { root@localhost } notification_email_from kaadmin@localhost smtp_server 127.0.0.1 smtp_connect_timeout 30 router_id LVS_DEVEL } vrrp_script chk_haproxy { script "killall -0 haproxy" interval 1 weight -2 } vrrp_instance VI_1 { state BACKUP 这台把master改成 backup interface eth0 virtual_router_id 200 priority 99 优先级调的比上一个低 advert_int 1 authentication { auth_type PASS auth_pass 11112222 } track_script { chk_haproxy } virtual_ipaddress { 192.168.1.200 } } vrrp_instance VI_2 { state MASTER 本台的这个要调成MASTER,上个是backup interface eth0 virtual_router_id 57 priority 100 这个优先级也要高于上个 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.1.201 } notify_master "/etc/keepalived/notify.sh master" notify_backup "/etc/keepalived/notify.sh backup" notify_fault "/etc/keepalived/notify.sh fault" }
注意:
notify_master
"/etc/keepalived/notify.sh master"
notify_backup
"/etc/keepalived/notify.sh backup"
notify_fault
"/etc/keepalived/notify.sh fault"
3个状态分别要执行的脚本,只能放在 MASTER中,原因是:因为是互为主从,每个主的都会有个另外一个主的从,如果
把这 “3个状态执行脚本” 写入到从的区域中,那么另外一个主的从状态就会执行这个脚本,因为就会停掉所要高可用的
程序,这就造成了,两个VIP全部转移到其中一个服务器上去。
我们来验证下,如果keepalived和haproxy分别宕机,vip会不会转移:
在两个节点上都启动 keepalived和haproxy服务
1 2 3 4 | [root@node2 ~]# service haproxy start Starting haproxy: [ OK ] [root@node2 ~]# service keepalived start Starting keepalived: [ OK ] |
以下为正常情况:
keepalived 1:
keepalived 2:
我们来模拟让第一个haproxy停止掉,再看下,VIP会不会全到 keepalived 2上面去:
1 2 | [root@node2 ~]# service haproxy stop Stopping haproxy: [ OK ] |
查看keepalived 1 和 keepalived 2
看,都过来了。。。。
验证负载均衡很动静分离
我们给3个web服务不同的网页
1、给apache static一个静态页面,来验证如果请求的不是以 .php结尾的网页文件都定向到这太服务器上来
2、给apache dynamic 1 、2 分别两个 index.php ,实现对动态网页的负载均衡
我们给apache static 一个符合-i .jpg .gif .png .css .js的网页,就给个图片网页吧
apache static
1 | scp 1 .png root@ 192.168 . 1.100 :/ var /www/html |
apache dynamic 1
vim /var/www/html/index.php 192.168.1.101 <?php phpinfo(); ?>
apache dynamic 2
vim /var/www/html/index.php 192.168.1.102 <?php phpinfo(); ?>
1、我们来请求 1.png 结尾的静态文件
2、我们来请求 .php结尾的页面
如此看来,已经对以.php的动态页面做了负载均衡了
我们再通过 192.168.1.201 这个虚拟 ip 访问试试:
由此看来,也实现了双主模型了,两个haproxy同时可以服务了。。。
3、我们来看看状态页面