varnish负载均衡实现

最新推荐文章于 2022-06-16 21:46:39 发布

转载最新推荐文章于 2022-06-16 21:46:39 发布 · 2k 阅读

文章标签：

#负载均衡 #服务器 #encoding #byte #delete #web

本文介绍了一个具体的Varnish VCL配置文件实例，详细解释了如何定义后端服务器及其负载均衡策略，并展示了如何设置缓存清理权限、请求处理流程及缓存策略等关键配置。

#这个是varnish的VCL配置文件，保存于DIR/varnish/etc/varnish/目录中。主要用于定义varnish接到请求后的处理方式和请求的方向。
#定义后台服务器
backend web01{
.host = "192.168.10.239"; #后台服务器的IP
.port = "80"; #端口
.connect_timeout = 1s; #连接超时时间
.first_byte_timeout = 5s; #
.between_bytes_timeout = 2s; #两次对服务器请求的间隔时间
.probe = { #定义对后台服务器的探针检测
.url = "/"; #检测的路径
.timeout = 0.3s; #检测超时时间
.window = 8;
.threshold = 3;
.initial = 3;
}
}
backend web02{
.host = "192.168.10.243";
.port = "80";
.connect_timeout = 1s;
.first_byte_timeout = 5s;
.between_bytes_timeout = 2s;
.probe = {
.url = "/";
.timeout = 0.3s;
.window = 8;
.threshold = 3;
.initial = 3;
}
}
#定义后台服务器组，并利用Round-Robin方式进行轮询。
director load round-robin {
{
.backend = web01;
}
{
.backend = web02;
}
}
#定义可以对varnish缓存进行清理的用户
acl purge{
"localhost";
}
sub vcl_recv{
if (req.request == "PURGE"){
if (!client.ip ~ purge){
error 405 "Not allowed.";
}
return (lookup);
}
if (req.http.host ~ "192.168.10.245"){
set req.backend = load;
}
if (req.restarts == 0){
if (req.http.x-forwarded-for) {
set req.http.X-Forwarded-For =
req.http.X-Forwarded-For "," client.ip;
}
else {
set req.http.X-Forwarded-For = client.ip;
}
}
if (req.request != "GET" && req.request != "HEAD" && req.request != "PUT" && req.request != "POST" && req.request != "TRACE" && req.request != "OPTIONS" && req.request != "DELETE") {
return (pipe);
}
elseif (req.request != "GET" && req.request != "HEAD") {
return (pass);
}
elseif ((req.request=="GET" || req.request=="HEAD")&& req.url ~ "\.(png|gif|jpeg|swf|css|js|jpg)$"){
return (lookup);
}
else {
return (pipe);
}
if (req.http.Accept-Encoding){ #更改主机头提高缓存命中率
if(req.url ~"\.(jpg|jpge|png|gif)$"){
#No point in compressing these
remove req.http.Accept-Encoding;
}
elseif (req.http.Accept-Encoding ~ "gzip"){
set req.http.Accept-Encoding = "gzip";
}
elseif (req.http.Accept-Encoding ~ "deflate"){
set req.http.Accept-Encoding = "deflate";
}
else{
#unknow algorithm
remove req.http.Accept-Encoding;
}
}
}
sub vcl_pipe {
return (pipe);
}
sub vcl_pass {
return (pass);
}
sub vcl_hash {
set req.hash += req.url;
if (req.http.host) {
set req.hash += req.http.host;
}
else {
set req.hash += server.ip;
}
return (hash);
}
sub vcl_hit{
if (!obj.cacheable){
return (pass);
}
else {
return (deliver);
}
}
sub vcl_miss{
return (fetch);
}
sub vcl_fetch{
if (!beresp.cacheable) {
return (pass);
}
elseif (beresp.http.Set-Cookie) {
return (pass);
}
else {
return (deliver);
}
}
sub vcl_deliver {
return (deliver);
}
sub vcl_error {
set obj.http.Content-Type = "text/html; charset=utf-8";
synthetic {"
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>"{ obj.status " " obj.response }"</title>
</head>
<body>
<h1>Error "{ obj.status "" obj.response }"</h1>
<p>"{ obj.response}"</p>
<h3>Guru Meditation:</h3>
<p>XID: "{req.xin}" </p>
<hr>
<p>Varnish cache server</p>
</body>
</html>
"};
return (deliver);
}