Node.js dns.resolve "bug"?

_readme.md

I'm pulling company data from a file server, simon.int (dataDomain). While connected to our network via ethernet cable, or our internal wireless network I can access the file server via both browser, and via Node.js dns.resolve. If I'm outside our network I can't connect via either browser or Node's dns.resolve method (as expected). The problem arises when I connect to our internal network via VPN. I can open simon.int in a browser, I can ping it, etc. yet dns.resolve returns an error when trying to connect to it.

I feel that this is a bug, but I can't find documentation of any sort of expectation of how it should work. I'm trying to determine whether I should report it as a bug, or if my expectation of it is incorrect. I ended up getting around it by making a jQuery AJAX HEAD request just to see if the server was available or not (works great).

I'd love input on this subject, or a pointer in the right direction.

A fellow developer suggested that perhaps it amounted to the user that Node was running as vs "me" accessing simon.int via ping or the browser.

FYI my version of Node:

$ node --version
v0.10.26

checkConnection.js

publicMethods.checkConnection = function(success, failure, bypass) {
    /*
    Checks to make sure application has an active connection
    to the domain hosting the data file
    */
    var dataDomain = 'simon.int';
    $.ajax('http://' + dataDomain, {type: 'HEAD'})
    .done(function(d){
        success();
    })
    .fail(function(e){
        if (publicMethods.checkExistingDataFile()) {
            bypass();
        } else {
            failure();
        }
    });

    // the code below is the desired implementation but for some reason
    // Node.js' dns.resolve method fails when connecting to simon.int
    // Is it our implementation or a bug in Node? Either way, good old jQuery
    // saves the day. Would be nice to revert to this method at some point
    // in the future.

    // var dns = require("dns");
    // dns.resolve(dataDomain, function(error, addr){
    //     if (error) {
    //         if (publicMethods.checkExistingDataFile()) {
    //             bypass();
    //         } else {
    //             failure();
    //         }
    //     } else {
    //         success();
    //     }
    // });
};

I suspect this is a bug.

C-Ares has to query Windows to ask “What DNS server should I use?” which most likely ends up here: https://github.com/bagder/c-ares/blob/master/ares_init.c#L914

Maybe it's not correctly interpreting the result when VPN is enabled, and connecting to the wrong DNS server as a result. Wireshark would tell the story, I bet.