DNS cannot resolve IPv6

[DoctorKrolic]

Description

BCL Dns class APIS doesn't seem to be able to resolve IPv6 even for basic well-known host names

Reproduction Steps

using System.Net;

var addrs = Dns.GetHostAddresses("google.com");
foreach (var addr in addrs)
{
    Console.WriteLine(addr);
}

Expected behavior

Same address list as I get via Resolve-DnsName powershell command:

2a00:1450:4025:800::65
2a00:1450:4025:800::8a
2a00:1450:4025:800::71
2a00:1450:4025:800::66
142.250.109.102
142.250.109.100
142.250.109.113
142.250.109.138
142.250.109.139
142.250.109.101

Actual behavior

Program prints only IPv4 addresses:

142.250.120.102
142.250.120.113
142.250.120.139
142.250.120.100
142.250.120.138
142.250.120.101

Regression?

Same behavior on .NET Framework 4.8.1, .NET 8, 10 and 11

Known Workarounds

I don't think there are any. When I specify AddressFamily.InterNetworkV6 as the second parameter of Dns.GetHostAddresses I get System.Net.Sockets.SocketException (0x00002AFC) thrown

Configuration

.NET Framework 4.8.1, .NET 8, 10 and 11
Windows 11 25H2 (26200.8457) x64, didn't check on other OSes

Other information

No response

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[MichalPetryka]

It does resolve IPv6 even when my ISP doesn't provide it for me so it must be something with your setup.

[wfurt]

Can you check Socket.OSSupportsIPv6 @DoctorKrolic? The name resolution simply calls the underlying resolver.

[dotnet-policy-service]

This issue has been marked needs-author-action and may be missing some important information.