C# server that supports IPv6 and IPv4 on the same port

Question

Is it possible to have a Socket that listens and accepts both IPv6 and IPv4 clients? I used a IPv6 socket in C# hoping that it would automatically be backwards compatible but IPv4 clients cause an invalid ip address exception.

score 7 · Accepted Answer · edited Feb 24 '19 at 15:07

7

Have a look here. You can accept IPv4 clients as well as IPv6 clients with the one server socket.

edited Feb 24 '19 at 15:07

Pixelfish

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answered Aug 17 '09 at 02:44

Matthew Iselin

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silky: I'd say you're right. I've totally rewritten my answer. – Matthew Iselin Aug 17 '09 at 03:01
Looks like one of your links may have evaporated. – Mar 17 '14 at 20:58

score 7 · Answer 2 · answered Aug 07 '17 at 08:35

Set the socket's IPv6Only option to false:

Socket MySocket = new Socket(AddressFamily.InterNetworkV6, SocketType.Stream, ProtocolType.Tcp);
MySocket.SetSocketOption(SocketOptionLevel.IPv6, SocketOptionName.IPv6Only, false);

(taken from Matthew Iselin's second link)

C# server that supports IPv6 and IPv4 on the same port

2 Answers2

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