VCL-static

vcl 4.0;
import http;

# We define the origin servers
# assumption they listen on port 80, please change it if not true
backend origin_a {
    .host = "103.234.96.112";
    .port = "80";
}

backend origin_b {
    .host = "103.226.154.55";
    .port = "80";
}

backend origin_c {
    .host = "103.113.11.126";
    .port = "80";
}

backend origin_d {
    .host = "58.82.215.198";
    .port = "80";
}

sub vcl_init {
                new rr = directors.round_robin();
                rr.add_backend(origin_a);
                rr.add_backend(origin_b);
                rr.add_backend(origin_c);
                rr.add_backend(origin_d);
        }

sub vcl_recv {
    set req.backend_hint = rr.backend();
}

sub vcl_hash {
    hash_data(req.url);
    return (lookup);
}

sub vcl_hit {
    set req.http.X-status = "HIT";
}

sub vcl_miss {
    set req.http.X-status = "MISS";

    # Prefetch

}

sub vcl_pass {
    set req.http.X-status = "PASS";
}

sub vcl_backend_response {
    set beresp.ttl = 120s;
    set beresp.grace = 60s;
    if (bereq.url exe;wmv;mp3;wma;ogg;swf;flv;mp4;avi;mpg;mpeg;f4v;rmvb;rm;3gp;img;cur;gif;png;jpe;ico;bmp;jpeg;jpg;rpm;deb;tar;gz;bin;bz2;zip;rar;ipa;apk;jar;sis;xap;msi;cab;7z;pdf;doc;docx;xls;xlsx;ppt;pptx;txt;css;js;wav) {
        set beresp.ttl = 365d;
        set beresp.grace = 24h;
    }
    
    unset beresp.http.X-Varnish;
    unset beresp.http.Via;

    # Retry on error
    if (beresp.status >= 500) {
        return (retry);
    }

    return (deliver);
}

# Retry on error
sub vcl_backend_error {
    return (retry);
}


sub vcl_deliver {
    if (bereq.url exe;wmv;mp3;wma;ogg;swf;flv;mp4;avi;mpg;mpeg;f4v;rmvb;rm;3gp;img;cur;gif;png;jpe;ico;bmp;jpeg;jpg;rpm;deb;tar;gz;bin;bz2;zip;rar;ipa;apk;jar;sis;xap;msi;cab;7z;pdf;doc;docx;xls;xlsx;ppt;pptx;txt;css;js;wav) {
        set resp.http.Cache-Control = "max-age=31536000, s-maxage=31536000";
    }
    # Cache status
    set resp.http.X-cache-edge = obj.hits + " (" + req.http.X-status + ":" +
        server.identity + ") " + resp.http.X-cache;
}