HttpContext.Current.Request.Url.Authority giving wrong Authority names

I have two production web servers that are load balanced and that sit in a DMZ. I have a form that needs to open another form based on certain criteria. One of the servers works fine and gives the full authority name ie, "host.n.n.com". The other prod server only returns "host" and as a result the page cannot be found. Here's the code i'm using:

urlString.Append(url.Scheme);
urlString.App开发者_StackOverflowend("://");
urlString.Append(url.Authority);
urlString.Append("/somedir/anotherdir/");
urlString.Append(formName + ".aspx");

server 1(working) comes back with http://host.n.n.com/somedir/anotherdir/formName.aspx server 2(broke) comes back with http://host/somedir/anotherdir/formName.aspx

IIS appears to be onfigured the same across both servers.

Thanks in advance for any help

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The Authority property comes from the request itself.

If the request from the user is made from 'host.n.n.com' or 'host' This is what the property will reflect. You can test this locally by using http://localhost/yoursite/page.aspx vs http://yourcomputername/yoursite/page.aspx. The same page will return 'localhost` and 'yourcomputername' respectively.

Why not make the URL a configuration setting?