开发笔记:varnish实现缓存加速

一、采用varnish为nginx实现缓存加速
1、实验环境:
(1)一台varnish缓存服务器,一台nginx服务器
(2)关闭防火墙和selinux
2.配置varnish
(1)修改varnish配置文件:

创建目录:mkdir -pv /data/varnish/cache
修改属主:chown varnish.varnish /data/varnish/cache

(2)测试：


二、varnish实现动静分离
(1)varnish配置:

(2)测试:


(3)附件内容设置多个组，并做负载:

示例：
import directors
backend imgsrv1 {
.host = "192.168.10.11";
.port = "80";
}
backend imgsrv2 {
.host = "192.168.10.12";
.port = "80";
}
backend appsrv1 {
.host = "192.168.10.21";
.port = "80";
}
backend appsrv2 {
.host = "192.168.10.22";
.port = "80";
}
sub vcl_init {
new imgsrvs = directors.random();
imgsrvs.add_backend(imgsrv1,10);
imgsrvs.add_backend(imgsrv2,20);
new staticsrvs = directors.round_robin();
appsrvs.add_backend(appsrv1);
appsrvs.add_backend(appsrv2);
new appsrvs = directors.hash();
appsrvs.add_backend(appsrv1,1);
appsrvs.add_backend(appsrv2,1);
}
sub vcl_recv {
if (req.url ~ "(?i).(css|js)$" {
set req.backend_hint = staticsrvs.backend();
}
if (req.url ~ "(?i).(jpg|jpeg|png|gif)$" {
set req.backend_hint = imgsrvs.backend();
} else {
set req.backend_hint = appsrvs.backend(req.http.COOKIE);
}
}


安全检测:

.probe：定义健康状态检测方法；
.url：检测时要请求的URL，默认为”/";
.request：发出的具体请求；
.request =
"GET /.healthtest.html HTTP/1.1"
"Host: www.ww.com"
"Connection: close"
.window：基于最近的多少次检查来判断其健康状态；
.threshold：最近.window中定义的这么次检查中至有.threshhold定义的次数是成功的；成功阈值；
.interval：检测频度；
.timeout：超时时长；
.expected_response：期望的响应码，默认为200；
健康状态检测的配置方式：
probe PB_NAME { }
backend NAME = {
.probe = PB_NAME;
...
}