Varnish VCL : how can I switch on req. backend_hint？

Question

我有以下VCL:

vcl 4.0;

import std;
import directors;

backend one {
    .host = "localhost";
    .port = "3333";
}

backend two {
    .host = "localhost";
    .port = "3333";
}

sub vcl_init {
    new random_director = directors.random();
    random_director.add_backend(two, 10);
    random_director.add_backend(one, 8);
}

sub vcl_recv {

    std.log("start vcl_recv");

    set req.backend_hint = random_director.backend();
    if (req.backend_hint == one) {
        std.log("one");
    } else if (req.backend_hint == two) {
        std.log("two");
    } else {
        std.log("neither one");
    }

    std.log("end vcl_recv");
}

当我运行它时，输出始终是:

start vl_recv
neither one
end vcl_recv

如何正确检查以查看选择了哪个后端？

谢谢

Answer 1

在vcl_backend_fetch中，您应该可以访问bereq.backend.name
因此，移动代码，您可能会遇到类似以下内容的情况:

sub vcl_backend_fetch {
    if (bereq.backend.name == "one") {
       std.log("one");
    } else if (bereq.backend.name == "two") {
       std.log("two");
    } else {
       std.log("neither one");
    }
}