Testing IPv6 - not able to connect to local IPv6 only Wi-Fi network

You seem to be working on the assumption that the Internet Sharing-based DNS64/NAT64 test network requires IPv6 connectivity. That’s not the case. In fact, if you deploy it on a network with IPv6 connectivity, it won’t use that (r. 24142384). There’s a bunch of complexity here, so let’s start from fundamentals.

From the client device’s perspective there are three types of networks to consider:

• IPv4-only (A)

• IPv4 and IPv6, aka dual stack (B)

• IPv6-only, using DNS64/NAT64 to get at IPv4 servers (C)

Type A is the status quo. Type B is your current office setup (IPv4 and IPv6 are peers). Type C is the expected deployment network that App Review cares about.

The Internet Sharing-based DNS64/NAT64 test network is not an exact match for any of these. The IPv6 Connectivity section of my IPv6 and App Review post explains this difference.

Given that, hanging the Internet Sharing-based DNS64/NAT64 test network off your dual stack office network is kinda pointless; the test network won’t use the IPv6 connectivity that your network provides.

Finally, I should stress that the vast majority of problems that we see where an app works in the Internet Sharing-based DNS64/NAT64 test network but fails in App Review relates to DNS. DNS64/NAT64 network walks a DNS path that’s rarely used (it requires that the DNS say “No” in the correct way) and App Review’s DNS64/NAT64 gateway is less forgiving that it should be. My IPv6 and App Review post explains this in more detail, and shows how you can look for DNS problems like this.

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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Hi Eskimo,

I realize this is an older post, but we are running into issues with IPv6 and I am pretty sure it is a DNS issue as you have mentioned in this article. I have tried reproducing with the Mac NAT64 hotspot setup as well as on a T-Mobile US cellular network but have not been able to reproduce the error that was seen during the app review process. I have come across several support pages that say to use the Mac NAT64 network for testing but that it doesn't perfectly mimic the DNS64/NAT64 network use during app review. I have not yet been able to find a document that describes the DNS64/NAT64 network setup process that Apple uses for app reviews. This would be very helpful to have inorder to reproduce issues and ensure changes we are making to our produciton environment is actually going to resolve the app review issue. Can Apple publish the setup used for DNS64/NAT64 testing on an IPv6 only network?

Scott

Not covered here (last updated after this thread was created)?

https://developer.apple.com/library/content/documentation/NetworkingInternetWeb/Conceptual/NetworkingOverview/UnderstandingandPreparingfortheIPv6Transition/UnderstandingandPreparingfortheIPv6Transition.html

I have come across several support pages that say to use the Mac NAT64 network for testing but that it doesn't perfectly mimic the DNS64/NAT64 network use during app review.

Historically that was true, but they are a lot closer these days. You should read my Supporting IPv6-only Networks pinned post, and specifically the post linked to by FAQ#6. This explains this change and a bunch of other stuff as well.

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Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Hey Eskimo,

Thanks for the response. I read that article as well as the one linked to at FAQ#6. The article from FAQ#6 helped to identify the issue. We believe it is because the subdomain used for our app was incorrectly configured as an SOA, but we don't have a way to test this without resubmitting another app for review. The MacNAT64 didn't catch this issue.

Any insight as to how Apple sets up its IPv6 only network for testing would be greatly helpful in reproducing these issues in the future and verify DNS changes work before going to produciton.

Scott

Seems like all the links the articles are broken. The Eskimo must have moved to warmer climates.

Seems like all the links the articles are broken.

Yeah, that’s an annoying artefact of one of DevForums’s various platform migrations. I’ve fixed the links in my first reply on this thread, and that should be sufficient to find the other stuff.

The Eskimo must have moved to warmer climates.

I wish (-:

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—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"