Ping and Hostname in Windows – DNS Troubleshooting Guide

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In my machine with windows OS installed, under system information, there are 3 pieces of information, namely, computer name : desktop-1, full computer name : desktop-1.d1.d2.d3 and domain: d1.d2.d3

When i try to ping this machine, "ping desktop-1", from another machine in the same network, ping automatically redirects/tries to ping desktop-1.d1.d2.d3

C:\Users>ping desktop-1
Pinging desktop-1.d1.d2.d3 [xx.xx.xx.xx] with 32 bytes of data:

……….

With respect to this, i need some clarifications:

  1. How does ping convert hostname to fully qualified domain name(FQDN)? Does it read the "Domain" field value from the OS and automatically attach desktop name with domain name and then ask the DNS server to find the ip of this FQDN?

  2. Suppose if the "Domain" field is not configured, then how does ping find the ip of the hostname?

  3. In other OS'es, like linux, where are these information configured?

Thanks in advance!

Best Answer

A shortname can be resolved by Windows as a NetBIOS name or as a DNS name (two different protocols).

NetBIOS resolution is broadcast-based (we're not going into that now because it's not in the scope of your question).

However, to be resolved as a DNS name, the shortname first has to be converted to an FQDN. This process is quite simple: Windows appends one or more suffixes to the shortname.

Now the question is: Where does Windows get the suffix from ?

The DNS suffix is provided via the network adapter properties (it can be configured by GPO too), or, it can be configured using DHCP's option 15 (it's a very convenient and easy way of distributing the DNS Domain Name).

If you want to learn more about the name resolution, you can read the Windows Name Resolution overview and follow the links in that document.

I'm not a specialist of Linux, but, as the DHCP option 15 is in the RFC (it's not a Microsoft-only thing), they should support it.