Get IPv4 addresses from Dns.GetHostEntry()

c# .net dns ipv6 ipv4
zombat picture zombat · Jun 29, 2009 · Viewed 105.1k times · Source

I've got some code here that works great on IPv4 machines, but on our build server (an IPv6) it fails. In a nutshell:

IPHostEntry ipHostEntry = Dns.GetHostEntry(string.Empty);

The documentation for GetHostEntry says that passing in string.Empty will get you the IPv4 address of the localhost. This is what I want. The problem is that it's returning the string "::1:" on our IPv6 machine, which I believe is the IPv6 address.

Pinging the machine from any other IPv4 machine gives a good IPv4 address... and doing a "ping -4 machinename" from itself gives the correct IPv4 address.... but pinging it regularly from itself gives "::1:".

How can I get the IPv4 for this machine, from itself?

Answer

Remus Rusanu picture Remus Rusanu · Jun 29, 2009

Have you looked at all the addresses in the return, discard the ones of family InterNetworkV6 and retain only the IPv4 ones?

Related questions

Get domain name

My computer is in a Domain (Active Directory) and I need to get the domain name dynamically. I found the following code on the internet: SelectQuery query = new SelectQuery("Win32_ComputerSystem"); using (ManagementObjectSearcher searcher = new ManagementObjectSearcher(query)) { foreach (ManagementObject mo …

Read More
How to get mx records for a dns name with System.Net.DNS?

Is there any built in method in the .NET library that will return all of the MX records for a given domain? I see how you get CNAMES, but not MX records.

Read More
What does Dns.GetHostEntry Method(String) actually do?

I can't find any proper description in the documentation for what this actually does. Does it check for the existence of A records or CNAME records or both? My understanding is that in .NET 4, this throws a SocketException if the …

Read More