Can ping by IP, and FQDN, but not hostname over SSL VPN

Question

I am connecting to a server at another location, I cannot access network shares by hostname (\server\share). I decided to ping the server to see if I could reach it, no luck. Pinged by IP and got a response, same with fully qualified domain name. I can access by hostname if I add the server to my hosts file.

The server I am connecting to is my DNS server, I am connecting over a Sophos Astaro SSL VPN. The VPN connects fine, ipconfig /all shows the correct DNS settings.

I can also ping by hostname locally which leads me to think that the issues lies in the Astaro device.

I need to be able to access these shares by hostname, all of my users are configured to use hostname.

I feel like this is a simple issue, I have just been banging my head against the desk, I think I am burnt out.

Does anyone have any information that might point me in the right direction?

Thanks.

Answer 1

Your DNS works just fine. What you want to do is to add a search domain so that any single hostname is automatically completed with the search domain, and the outgoing query is for a FQDN, which we already know to be working on your network.

If your local and remote LANs are called, for instance, campus2.mycollege.edu and campus1.mycollege.edu, then add the second search domain, campus1.mycollege.edu, to your Windows pc, as follows:

• Control Panel → Network and Internet → Network and Sharing Center.
• Click on Change Adapter Settings on the left side.
• Right-click on your network adapter (normally "Local Area Connection" or "Wireless Network Connection") and select Properties.
• Select Internet Protocol version 4 (TCP/IPv4) and click on the Properties button.
• On the General tab, click on the Advanced… button.
• In the Append this DNS suffixes list, add campus1.mycollege.edu.

You may now try it, to see whether this works (it very much should).

This is good for testing. But how do you implement this in an automatic way? You will have either to change the configuration of your VPN server so that an option describing the new search domain is pushed to all users, or you change your local DNS so that this new, extra search domain is added to the existing one. Both are implementation-specific, but for instance by Googling I found this for enabling search domains through the VPN, which should be relevant to you.

Answer 2

There is a lot of information that would be needed to resolve this. But just from what you described, I would say it most likely an issue with your firewall allowing DNS. Things I would check.

Port 53 UDP and TCP allowed both directions.

From the VPN device, is DNS working? if so track it back from there to your local PC. It should be a direct tunnel to your network were DNS is running.

Something to try. Edit your host file to point to that IP address.