本文主要是介绍Varnish高性能HTTP加速服务器教程，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！
主机环境：
- rhel6.5 selinux and iptables disabled
实验主机：
| 主机名 | IP | 服务 |
|---|---|---|
| server1 | 172.25.254.1 | varnish |
| server2 | 172.25.254.2 | apache |
| server3 | 172.25.254.3 | apache |
Varnish工作原理图
VCL (Varnish Configuration Language)处理流程图
处理过程大致分为如下几个步骤:
- Receive 状态,也就是请求处理的入口状态,根据 VCL 规则判断该请求应该是 Pass 或 Pipe,或者进入 Lookup(本地查询)。
- Lookup 状态,进入此状态后,会在 hash 表中查找数据,若找到,则进入 Hit 状态,否则进入 miss 状态。
- Pass 状态,在此状态下,会进入后端请求,即进入 fetch 状态。
- Fetch 状态,在 Fetch 状态下,对请求进行后端的获取,发送请求,获得数据,并进行本地的存储。
- Deliver 状态, 将获取到的数据发送给客户端,然后完成本次请求。
设计思想：firefox -> hosts/dns -> varnish -> httpd
varnish–server1
- 安装
- http://varnish-cache.org/releases/install_redhat.html#install-redhat
[root@server1 ~]# yum install -y varnish-3.0.5-1.el6.x86_64.rpm varnish-libs-3.0.5-1.el6.x86_64.rpm - 配置 varnish 服务端口
[root@server1 ~]# vim /etc/sysconfig/varnishVARNISH_LISTEN_PORT=80- 配置一个后端服务器
[root@server1 ~]# vim /etc/varnish/default.vcl
backend default {.host = "172.25.254.2";.port = "80";
}- 查看缓存命中情况
[root@server1 ~]# vim /etc/varnish/default.vcl
sub vcl_deliver {if (obj.hits > 0) {set resp.http.X-Cache = "HIT from test cache";}else {set resp.http.X-Cache = "MISS from test cache";}return (deliver);}- 开启服务
[root@server1 ~]# /etc/init.d/varnish startapache–server2
- 安装apache
[root@server2 ~]# yum install -y httpd- 编写前端文件
[root@server2 ~]# cat /var/www/html/index.html
<h1>Welcome to www.westos.org !!</h1>- 开启服务
[root@server2 ~]# /etc/init.d/httpd start物理机测试
- 添加解析
[root@fundation20 Desktop]# cat /etc/hosts
172.25.254.1 server1 www.westos.org - 测试
##未命中
[root@fundation20 Desktop]# curl -I www.westos.org
HTTP/1.1 200 OK
Server: Apache/2.2.15 (Red Hat)
Last-Modified: Tue, 13 Feb 2018 00:46:57 GMT
ETag: "20331-26-5650d54eefd0e"
Content-Type: text/html; charset=UTF-8
Content-Length: 38
Accept-Ranges: bytes
Date: Tue, 13 Feb 2018 02:09:16 GMT
X-Varnish: 120543320
Age: 0
Via: 1.1 varnish
Connection: keep-alive
X-Cache: MISS from test cache##命中
[root@fundation20 Desktop]# curl -I www.westos.org
HTTP/1.1 200 OK
Server: Apache/2.2.15 (Red Hat)
Last-Modified: Tue, 13 Feb 2018 00:46:57 GMT
ETag: "20331-26-5650d54eefd0e"
Content-Type: text/html; charset=UTF-8
Content-Length: 38
Accept-Ranges: bytes
Date: Tue, 13 Feb 2018 02:09:18 GMT
X-Varnish: 120543321 120543320
Age: 2
Via: 1.1 varnish
Connection: keep-alive
X-Cache: HIT from test cache通过 varnishadm 手动清除缓存
[root@server1 ~]# varnishadm ban.url .*$ #清除所有[root@server1 ~]# varnishadm ban.url /index.html #清除 index.html 页面缓存[root@server1 ~]# varnishadm ban.url /admin/$ #清除 admin 目录缓存定义多个不同域名站点的后端服务器
- varnish–server1
[root@server1 ~]# vim /etc/varnish/default.vcl
#配置两个后端服务器
backend web1 {.host = "172.25.254.2";.port = "80";
}
backend web2 {.host = "172.25.254.3";.port = "80";
}
#当访问 www.westos.org 或 westos.org 域名时从 web1 上取数据；
#访问 bbs.westos.org 域名时到 web2 取数据；
#访问其他，页面报错。sub vcl_recv {if (req.http.host ~ "^(www.)?westos.org") {set req.http.host = "www.westos.org";set req.backend = web1;} elsif (req.http.host ~ "^bbs.westos.org") {set req.backend = web2;} else {error 404 "westos cache";}}##重启服务[root@server1 ~]# /etc/init.d/varnish restartStopping Varnish Cache: [ OK ]Starting Varnish Cache: [ OK ]- apache–server2
[root@server2 ~]# cat /var/www/html/index.html
<h1>Welcome to www.westos.org from server2 !!</h1>[root@server2 ~]# /etc/init.d/httpd restart- apache–server3
[root@server3 ~]# yum install -y httpd[root@server3 ~]# cat /var/www/html/index.html
<h1>Welcome to bbs.westos.org from server3 !!</h2>[root@server3 ~]# /etc/init.d/httpd start物理机测试
- 添加解析
[root@fundation20 Desktop]# cat /etc/hosts
172.25.254.1 server1 www.westos.org westos.org bbs.westos.org- 浏览器测试
负载均衡
- varnish–server1
[root@server1 ~]# vim /etc/varnish/default.vcl
#配置两个后端服务器
backend web1 {.host = "172.25.254.2";.port = "80";
}
backend web2 {.host = "172.25.254.3";.port = "80";
}
##把两个后端聚合为一个组,并检测后端健康状况
director lb round-robin {{ .backend = web1; }{ .backend = web2; }
}
sub vcl_recv {if (req.http.host ~ "^(www.)?westos.org") {set req.http.host = "www.westos.org";set req.backend = lb; return(pass); ##为了测试方便,不进行缓存} elsif (req.http.host ~ "^bbs.westos.org") {set req.backend = web2;} else {error 404 "westos cache";}}[root@server1 ~]# /etc/init.d/varnish restart
Stopping Varnish Cache: [ OK ]
Starting Varnish Cache: [ OK ]- apache–server2
[root@server2 ~]# cat /var/www/html/index.html
<h1>Welcome to www.westos.org from server2 !!</h1>[root@server2 ~]# /etc/init.d/httpd restart- apache–server3
#搭建虚拟主机，保留原/var/www/html/index.html
[root@server3 ~]# vim /etc/httpd/conf/httpd.conf #打开虚拟主机服务
NameVirtualHost *:80 #去掉注释##添加到最后
<VirtualHost *:80>DocumentRoot /var/www/htmlServerName bbs.westos.org
</VirtualHost><VirtualHost *:80>DocumentRoot /wwwServerName www.westos.org
</VirtualHost>[root@server3 ~]# mkdir /www
[root@server3 ~]# vim /www/index.html
<h1>Welcome to www.westos.org from server3 !!</h1>[root@server3 ~]# /etc/init.d/httpd restart##添加本地解析
[root@server3 ~]# cat /etc/hosts
172.25.254.3 server3 www.westos.org bbs.westos.org ##测试虚拟机主机
[root@server3 ~]# curl www.westos.org
<h1>Welcome to www.westos.org from server3 !!</h1>
[root@server3 ~]# curl bbs.westos.org
<h1>Welcome to bbs.westos.org from server3 !!</h2>物理机测试：
- 查看解析
[root@fundation20 Desktop]# cat /etc/hosts
172.25.254.1 server1 www.westos.org westos.org bbs.westos.org- 浏览器测试
- 终端测试
[root@fundation20 Desktop]# for i in {1..6}; do curl www.westos.org ;done
<h1>Welcome to www.westos.org from server2 !!</h1>
<h1>Welcome to www.westos.org from server3 !!</h1>
<h1>Welcome to www.westos.org from server2 !!</h1>
<h1>Welcome to www.westos.org from server3 !!</h1>
<h1>Welcome to www.westos.org from server2 !!</h1>
<h1>Welcome to www.westos.org from server3 !!</h1>
这篇关于Varnish高性能HTTP加速服务器教程的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！
